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122-570: QuickDraw was grounded in the Apple Lisa 's LisaGraf of the early 1980s and was designed to fit well with the Pascal -based interfaces and development environments of the early Apple systems. In addition, QuickDraw was a raster graphics system, which defines the pixel as its basic unit of graphical information. This is in contrast to vector graphics systems, where graphics primitives are defined in mathematical terms and rasterized as required to

244-456: A graphical user interface (GUI) to be sold commercially. It uses a Motorola 68000 CPU clocked at 5 MHz and has 1 MB of RAM. It can be upgraded to 2 MB and later shipped with as little as 512 kilobytes. The CPU speed and model were not changed from the release of the Lisa 1 to the repackaging of the hardware as Macintosh XL. The real-time clock uses a 4-bit integer and the base year

366-623: A 12-inch (30 cm) screen. Lisa's printer support includes Apple's Dot Matrix , Daisy Wheel , and ImageWriter dot matrix printers, and Canon 's new color inkjet technology. The original Lisa, later called the Lisa 1, has two FileWare 5.25-inch double-sided variable-speed floppy disk drives, more commonly known by Apple's codename "Twiggy". They have what was then a very high capacity of approximately 871 kB each, but are unreliable and use proprietary diskettes. Competing systems with high diskette data storage have much larger 8" floppy disks, seen as cumbersome and old-fashioned for

488-417: A GrafPort for clipping , or drawn filled or framed like any other shape. A series of framed shapes and connected lines may be combined into a Region. A Region need not consist of a contiguous set of pixels - disconnected regions are possible and common. Although regions could allow powerful graphic manipulations they are limited by the current implementation that restricts the maximum region data storage size to

610-408: A GrafPort, and off-screen ports could also exist. The GrafPort defined a coordinate system . In QuickDraw, this had a resolution of 16 bits , giving 65,536 unique vertical and horizontal locations. These are numbered from -32,767 on the extreme left (or top), to +32,767 on the extreme right (or bottom). A window was usually set up so that the top, left corner of its content area was located at 0,0 in

732-462: A Lisa from the estate of Microsoft co-founder Paul Allen was sold for $ 882,000. Data compression In information theory , data compression , source coding , or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless . Lossless compression reduces bits by identifying and eliminating statistical redundancy . No information

854-589: A color depth of 1, 2, 4, 8, 15 and 24 bits, yielding 2, 4, 16, 256, 32,768 and 16,777,216 colors respectively, or 4, 16 and 256 scales of grey. QuickDraw took care of managing the resampling of colors to the available color depths of the actual video hardware, or transfer between offscreen image buffers, including optionally dithering images down to a lower depth to improve image quality. A set of color sampling utilities were also added so that programmers could generate optimal color palettes for use with indexed video devices. The architecture of QuickDraw had always allowed

976-469: A consumer system. Lisa 1's innovations include block sparing, to reserve blocks in case of bad blocks, even on floppy disks. Critical operating system information has redundant storage, for recovery in case of corruption. The first hardware revision, the Lisa 2, was released in January 1984 and was priced between $ 3,495 and $ 5,495 . It was much less expensive than the original model, and dropped

1098-403: A document-oriented workflow. The hardware is more advanced overall than the following Macintosh, including hard disk drive support, up to 2  megabytes (MB) of random-access memory (RAM), expansion slots, and a larger, higher-resolution display. Lisa's CPU and the storage system were strained by the complexity of the operating system and applications, especially its office suite , and by

1220-530: A fact that enabled the Macintosh to practically invent desktop publishing . Similar to a subclass , the Window data structure began with the associated GrafPort, thus basically making windows exchangeable with any GrafPort. While convenient, this made it easy to write erroneous code that passed an offscreen graphics port into API that expected a full-blown window. QuickDraw started life as Lisa Graf as part of

1342-505: A five-megabyte hard drive . It was affected by its high price, insufficient software, unreliable FileWare ( codename Twiggy) floppy disks , and the imminent release of the cheaper and faster Macintosh . Only 60,000 Lisa units were sold in two years. Lisa was considered a commercial failure but with technical acclaim, introducing several advanced features that reappeared on the Macintosh and eventually IBM PC compatibles . These include an operating system with memory protection and

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1464-494: A form of LPC called adaptive predictive coding (APC), a perceptual coding algorithm that exploited the masking properties of the human ear, followed in the early 1980s with the code-excited linear prediction (CELP) algorithm which achieved a significant compression ratio for its time. Perceptual coding is used by modern audio compression formats such as MP3 and AAC . Discrete cosine transform (DCT), developed by Nasir Ahmed , T. Natarajan and K. R. Rao in 1974, provided

1586-415: A further refinement of the direct use of probabilistic modelling , statistical estimates can be coupled to an algorithm called arithmetic coding . Arithmetic coding is a more modern coding technique that uses the mathematical calculations of a finite-state machine to produce a string of encoded bits from a series of input data symbols. It can achieve superior compression compared to other techniques such as

1708-460: A huge versioned document collection, internet archival, etc. The basic task of grammar-based codes is constructing a context-free grammar deriving a single string. Other practical grammar compression algorithms include Sequitur and Re-Pair . The strongest modern lossless compressors use probabilistic models, such as prediction by partial matching . The Burrows–Wheeler transform can also be viewed as an indirect form of statistical modelling. In

1830-597: A lossily compressed file for some purpose usually produces a final result inferior to the creation of the same compressed file from an uncompressed original. In addition to sound editing or mixing, lossless audio compression is often used for archival storage, or as master copies. Lossy audio compression is used in a wide range of applications. In addition to standalone audio-only applications of file playback in MP3 players or computers, digitally compressed audio streams are used in most video DVDs, digital television, streaming media on

1952-400: A lossy format and a lossless correction; this allows stripping the correction to easily obtain a lossy file. Such formats include MPEG-4 SLS (Scalable to Lossless), WavPack , and OptimFROG DualStream . When audio files are to be processed, either by further compression or for editing , it is desirable to work from an unchanged original (uncompressed or losslessly compressed). Processing of

2074-486: A marketing consultancy firm to find names to replace "Lisa" and "Macintosh" (at the time considered by Jef Raskin to be merely internal project codenames) and then rejected all of the suggestions. Privately, Hertzfeld and the other software developers used "Lisa: Invented Stupid Acronym", a recursive backronym , and computer industry pundits coined the term "Let's Invent Some Acronym" to fit Lisa's name. Decades later, Jobs told his biographer Walter Isaacson : "Obviously it

2196-521: A maximum row width of just 4,095 on 32-bit PixMaps, which became problematic for high-resolution graphics work. Later development (Mac OS 8.5/Carbon) eliminated this limitation but was not fully backward compatible. A Palette Manager was also added in Color QuickDraw which managed the arbitration of colors on indexed video devices. Most graphics primitives operations remained either unchanged (but would operate in color), or else new color versions of

2318-454: A picture was being recorded, the compressed data would be saved as part of the picture, for display when the picture was later drawn. The Image Compression Manager also added integration with ColorSync color matching. After this, apart from back-end changes to optimize for new processor architectures ( PowerPC ), QuickDraw remained largely unchanged throughout the rest of the life of the classic Mac OS. QuickDraw GX and QuickDraw 3D shared

2440-402: A representation of digital data that can be decoded to an exact digital duplicate of the original. Compression ratios are around 50–60% of the original size, which is similar to those for generic lossless data compression. Lossless codecs use curve fitting or linear prediction as a basis for estimating the signal. Parameters describing the estimation and the difference between the estimation and

2562-590: A result, speech can be encoded at high quality using a relatively low bit rate. This is accomplished, in general, by some combination of two approaches: The earliest algorithms used in speech encoding (and audio data compression in general) were the A-law algorithm and the μ-law algorithm . Early audio research was conducted at Bell Labs . There, in 1950, C. Chapin Cutler filed the patent on differential pulse-code modulation (DPCM). In 1973, Adaptive DPCM (ADPCM)

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2684-456: A significant extension of the original QuickDraw, was created. At this time Bill Atkinson was busy with HyperCard , so the Color QuickDraw work was done by Ernie Beernink (then still 23 years old): Apple's Dave Allen also credited Dave Fung. The original architecture lacked much provision for expandability, but using a series of hacks , the Apple developers managed to make the addition of color and

2806-450: A sixteen bit value and so are not practical as a general-purpose drawing composition tool and practical use at high resolution is also restricted. Regions underpin the rest of QuickDraw, permitting clipping to arbitrary shapes, essential for the implementation of multiple overlapping windows. Invented by Bill Atkinson, Regions were patented as a separate invention by Apple. [1] A region is specified (after initial creation) by an opening of

2928-418: A special case of data differencing . Data differencing consists of producing a difference given a source and a target, with patching reproducing the target given a source and a difference. Since there is no separate source and target in data compression, one can consider data compression as data differencing with empty source data, the compressed file corresponding to a difference from nothing. This

3050-530: A specific orientation, a ninety degree rotation of a region would require both detailed reverse engineering of the structure and extensive coding. A general rotation is impractical when compared to rotating the original source boundary description and simply creating a new region. However, the API includes conversion routines to and from BitMaps. (Bitmaps may also be rotated using well known methods, but with various degrees of image degradation depending upon angle chosen,

3172-408: A table-based compression model where table entries are substituted for repeated strings of data. For most LZ methods, this table is generated dynamically from earlier data in the input. The table itself is often Huffman encoded . Grammar-based codes like this can compress highly repetitive input extremely effectively, for instance, a biological data collection of the same or closely related species,

3294-458: A text-based appliance computer. Jobs redefined Macintosh as a cheaper and more usable form of Lisa's concepts, and led the skunkworks project with substantial motivation to compete in parallel with the Lisa team. In September 1981, below the announcement of the IBM PC , InfoWorld reported on Lisa, "McIntosh", and another Apple computer secretly under development "to be ready for release within

3416-417: A wedge. Text may be drawn in any installed font, in a variety of stylistic variations, and at any size and color. Depending on how the selected font is stored, text can be scaled in a variety of ways - TrueType fonts will scale smoothly to any size, whereas bitmap fonts do not usually scale well. An important feature of QuickDraw was support for transfer modes , which governed how a destination pixel value

3538-458: A year". It described Lisa as having a 68000 processor and 128KB RAM, and "designed to compete with the new Xerox Star at a considerably lower price". In May 1982, the magazine reported that "Apple's yet-to-be-announced Lisa 68000 network work station is also widely rumored to have a mouse ." Apple Confidential said, "Finally, and perhaps most damaging, even before the Lisa began shipping in June,

3660-772: A zip file's compressed size includes both the zip file and the unzipping software, since you can not unzip it without both, but there may be an even smaller combined form. Examples of AI-powered audio/video compression software include NVIDIA Maxine , AIVC. Examples of software that can perform AI-powered image compression include OpenCV , TensorFlow , MATLAB 's Image Processing Toolbox (IPT) and High-Fidelity Generative Image Compression. In unsupervised machine learning , k-means clustering can be utilized to compress data by grouping similar data points into clusters. This technique simplifies handling extensive datasets that lack predefined labels and finds widespread use in fields such as image compression . Data compression aims to reduce

3782-567: Is a desktop computer developed by Apple , produced from January 19, 1983 to August 1, 1986, and succeeded by Macintosh . It is generally considered the first mass-market personal computer operable through a graphical user interface (GUI). In 1983, a machine like the Lisa was still so expensive that it was primarily marketed to individual and small and medium-sized businesses as a groundbreaking new alternative to much bigger and more expensive mainframes or minicomputers such as from IBM , that either require additional, expensive consultancy from

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3904-492: Is available under an Apple Academic License Agreement. In April 1984, following the Macintosh launch, Apple introduced MacWorks, a software emulation environment enabling Lisa to run Macintosh System software and applications. MacWorks improved Lisa's market appeal. After the early Macintosh operating system first gained hard disk support, MacWorks also gained access to Lisa's hard disk in September. In January 1985, MacWorks

4026-506: Is called source coding: encoding is done at the source of the data before it is stored or transmitted. Source coding should not be confused with channel coding , for error detection and correction or line coding , the means for mapping data onto a signal. Data Compression algorithms present a space-time complexity trade-off between the bytes needed to store or transmit information, and the Computational resources needed to perform

4148-485: Is defined as 1980; the software won't accept any value below 1981, so the only valid range is 1981–1995. The real-time clock depends on a 4   ×   AA-cell NiCd pack of batteries that only lasts for a few hours when main power is not present. Prone to failure over time, the battery packs could leak corrosive alkaline electrolyte and ruin the circuit boards. The integrated monochrome black-on-white monitor has 720   ×   364 rectangular pixels on

4270-650: Is distinguished as a separate discipline from general-purpose audio compression. Speech coding is used in internet telephony , for example, audio compression is used for CD ripping and is decoded by the audio players. Lossy compression can cause generation loss . The theoretical basis for compression is provided by information theory and, more specifically, Shannon's source coding theorem ; domain-specific theories include algorithmic information theory for lossless compression and rate–distortion theory for lossy compression. These areas of study were essentially created by Claude Shannon , who published fundamental papers on

4392-416: Is lost in lossless compression. Lossy compression reduces bits by removing unnecessary or less important information. Typically, a device that performs data compression is referred to as an encoder, and one that performs the reversal of the process (decompression) as a decoder. The process of reducing the size of a data file is often referred to as data compression. In the context of data transmission , it

4514-411: Is on the order of 23 ms. Speech encoding is an important category of audio data compression. The perceptual models used to estimate what aspects of speech a human ear can hear are generally somewhat different from those used for music. The range of frequencies needed to convey the sounds of a human voice is normally far narrower than that needed for music, and the sound is normally less complex. As

4636-420: Is perceptually irrelevant, most lossy compression algorithms use transforms such as the modified discrete cosine transform (MDCT) to convert time domain sampled waveforms into a transform domain, typically the frequency domain . Once transformed, component frequencies can be prioritized according to how audible they are. Audibility of spectral components is assessed using the absolute threshold of hearing and

4758-426: Is processed. In the minimum case, latency is zero samples (e.g., if the coder/decoder simply reduces the number of bits used to quantize the signal). Time domain algorithms such as LPC also often have low latencies, hence their popularity in speech coding for telephony. In algorithms such as MP3, however, a large number of samples have to be analyzed to implement a psychoacoustic model in the frequency domain, and latency

4880-429: Is reduced, using methods such as coding , quantization , DCT and linear prediction to reduce the amount of information used to represent the uncompressed data. Lossy audio compression algorithms provide higher compression and are used in numerous audio applications including Vorbis and MP3 . These algorithms almost all rely on psychoacoustics to eliminate or reduce fidelity of less audible sounds, thereby reducing

5002-843: Is the basis for most animation and sprite-like effects on the Mac. QuickDraw provides a similar blitting function which is designed to implement scrolling within a GrafPort - the image in the port can be shifted to a new location without scaling (but with clipping if desired). Each graphics primitive operation is vectored through the StdProcs, a series of function pointers stored in the GrafPort. This limited polymorphism permits individual operations to be overridden or replaced by custom functions, allowing printer drivers to intercept graphics commands and translate them to suitable printer operations. In this way, QuickDraw can be rendered using PostScript ,

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5124-402: Is the same as considering absolute entropy (corresponding to data compression) as a special case of relative entropy (corresponding to data differencing) with no initial data. The term differential compression is used to emphasize the data differencing connection. Entropy coding originated in the 1940s with the introduction of Shannon–Fano coding , the basis for Huffman coding which

5246-435: Is used in digital cameras , to increase storage capacities. Similarly, DVDs , Blu-ray and streaming video use lossy video coding formats . Lossy compression is extensively used in video. In lossy audio compression, methods of psychoacoustics are used to remove non-audible (or less audible) components of the audio signal . Compression of human speech is often performed with even more specialized techniques; speech coding

5368-685: Is used in the GIF format, introduced in 1987. DEFLATE , a lossless compression algorithm specified in 1996, is used in the Portable Network Graphics (PNG) format. Wavelet compression , the use of wavelets in image compression, began after the development of DCT coding. The JPEG 2000 standard was introduced in 2000. In contrast to the DCT algorithm used by the original JPEG format, JPEG 2000 instead uses discrete wavelet transform (DWT) algorithms. JPEG 2000 technology, which includes

5490-462: The Apple II division upon taking Raskin's project. Newer Lisa models addressed its shortcomings but, even with a major price reduction, the platform failed to achieve sales volumes comparable to the much less expensive Mac. The Lisa 2/10 is the final model, then rebranded as the high-end Macintosh XL . Though the original documentation only refers to it as "The Lisa", Apple officially stated that

5612-535: The Apple III SOS operating system released three years earlier, Lisa's disk operating system also organizes its files in hierarchical directories. File system directories correspond to GUI folders, as with previous Xerox PARC computers from which Lisa borrowed heavily. Lisa was designed around a hard drive, unlike the first Macintosh. Lisa has two main user modes: the Lisa Office System and

5734-479: The Apple III of 1980. Apple sold a total of approximately 10,000 Lisa machines at US$ 9,995 (equivalent to about $ 30,600 in 2023) each, generating total sales of $ 100 million against a development cost of more than $ 150 million . The largest Lisa customer was NASA , which used LisaProject for project management. The Lisa 2 and its Mac ROM -enabled Macintosh XL version are the final two releases in

5856-523: The Apple Lisa development. For the Macintosh it was initially simplified, but then later extended. Originally, QuickDraw GrafPorts only supported a bit depth of 1, that is one bit per pixel, or black and white. This suited the built-in screen of the early Macintosh, with its fixed size of 512×342 pixels. Limited color was supported using a crude planar model, allowing QuickDraw to drive some types of dot-matrix printer that used multi-colored ribbons, but very few applications supported this feature. In 1987,

5978-630: The Internet , satellite and cable radio, and increasingly in terrestrial radio broadcasts. Lossy compression typically achieves far greater compression than lossless compression, by discarding less-critical data based on psychoacoustic optimizations. Psychoacoustics recognizes that not all data in an audio stream can be perceived by the human auditory system . Most lossy compression reduces redundancy by first identifying perceptually irrelevant sounds, that is, sounds that are very hard to hear. Typical examples include high frequencies or sounds that occur at

6100-587: The Macintosh II was launched, which was designed as a more conventional three-box design - Computer , monitor and keyboard all separate. Because the monitor was separate, and larger than the original Mac, the video architecture had to necessarily change. In addition, the Mac II took the Macintosh from black-and-white to full color. Apple also decided at this time to support a seamless desktop spanning multiple monitors, an industry first. Thus Color QuickDraw,

6222-589: The Macintosh Plus was introduced in 1986. The Lisa operating system features protected memory , enabled by a crude hardware circuit compared to the Sun-1 workstation (c. 1982), which features a full memory management unit. Motorola did not have an MMU (memory-management unit) for the 68000 ready in time, so third parties developed their own. Apple's is also the result of a cost-cutting compromise, with sluggish performance. Based, in part, on elements from

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6344-507: The Motion JPEG 2000 extension, was selected as the video coding standard for digital cinema in 2004. Audio data compression, not to be confused with dynamic range compression , has the potential to reduce the transmission bandwidth and storage requirements of audio data. Audio compression formats compression algorithms are implemented in software as audio codecs . In both lossy and lossless compression, information redundancy

6466-476: The University of Buenos Aires . In 1983, using the psychoacoustic principle of the masking of critical bands first published in 1967, he started developing a practical application based on the recently developed IBM PC computer, and the broadcast automation system was launched in 1987 under the name Audicom . 35 years later, almost all the radio stations in the world were using this technology manufactured by

6588-506: The desktop metaphor . Steve Jobs visited PARC in 1979 and was absorbed and excited by the revolutionary mouse-driven GUI of the Alto . By late 1979, Jobs successfully negotiated a sale of Apple stock to Xerox, in exchange for his Lisa team receiving two demonstrations of ongoing research projects at PARC. When the Apple team saw the demonstration of the Alto computer, they were able to see in action

6710-450: The discrete cosine transform (DCT). It was first proposed in 1972 by Nasir Ahmed , who then developed a working algorithm with T. Natarajan and K. R. Rao in 1973, before introducing it in January 1974. DCT is the most widely used lossy compression method, and is used in multimedia formats for images (such as JPEG and HEIF ), video (such as MPEG , AVC and HEVC) and audio (such as MP3 , AAC and Vorbis ). Lossy image compression

6832-506: The linear predictive coding (LPC) used with speech, are source-based coders. LPC uses a model of the human vocal tract to analyze speech sounds and infer the parameters used by the model to produce them moment to moment. These changing parameters are transmitted or stored and used to drive another model in the decoder which reproduces the sound. Lossy formats are often used for the distribution of streaming audio or interactive communication (such as in cell phone networks). In such applications,

6954-610: The probability distribution of the input data. An early example of the use of arithmetic coding was in an optional (but not widely used) feature of the JPEG image coding standard. It has since been applied in various other designs including H.263 , H.264/MPEG-4 AVC and HEVC for video coding. Archive software typically has the ability to adjust the "dictionary size", where a larger size demands more random-access memory during compression and decompression, but compresses stronger, especially on repeating patterns in files' content. In

7076-587: The "Offscreen Graphics World" or GWorld. The video buffer (PixMap) of a GWorld could be stored in main memory, or when available in unused parts of video ram where copying to the screen could be optimized for speed by avoiding the need to transfer a large amount of pixel data across the main memory bus. With the advent of QuickTime , QuickDraw gained the ability to deal with compressed raster data, such as JPEG . The QuickTime Image Compression Manager integrated closely with QuickDraw: in particular, image decompression calls were full-fledged QuickDraw drawing calls, and if

7198-573: The (opaque) storage of thread information and a new (non-polled) event structure. Everything seen on a classic Mac OS screen is drawn by QuickDraw, but the library itself is quite low level. The primitive objects it can draw are: Each of these objects (except text) may be drawn using a "pen", which can have any rectangular dimensions, pattern or color. Note that, because the pen is rectangular and axis-aligned, diagonal lines will end up thicker than horizontal or vertical ones. Shapes may be drawn filled or framed, using any pattern or color. A filled Arc forms

7320-508: The API, since all operations pertained to "the current port," but as the OS developed, this use of global state has also made QuickDraw much harder to integrate with modern design approaches such as multi-threading and pre-emptive multitasking . To address these problems, the Carbon API (a bridge between Mac OS 9 and Mac OS X) added additional parameters to some of the routines, allowing for

7442-476: The Lisa and wrote in February 1983 that it was "the most important development in computers in the last five years, easily outpacing [the IBM PC ]". It acknowledged that the $ 9,995 price was high, and concluded "Apple ... is not unaware that most people would be incredibly interested in a similar but less expensive machine. We'll see what happens". The Lisa was a commercial failure, the company's largest since

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7564-430: The Lisa had been hard work. He said the system's hard disk and RAM was a requirement and not a luxury, but that the system remains slow. He noted that, by 1989, Lisa's level of integration between applications had not yet been repeated by Apple. Original "Twiggy" based Lisa 1 systems command high prices at auction due to the scarcity of surviving examples. The auction record for a Lisa 1 was set on September 10, 2024, when

7686-617: The Lisa line, which was discontinued in April 1985. The Macintosh XL is a hardware and software conversion kit to effectively reboot Lisa into Macintosh mode. In 1986, Apple offered all Lisa and XL owners the opportunity to return their computer and pay $ 1,498 , in exchange for a Macintosh Plus and Hard Disk 20 . Reportedly, 2,700 working but unsold Lisa computers were buried in a landfill. The Macintosh project, led by Steve Jobs, borrowed heavily from Lisa's GUI paradigm and directly took many of its staff, to create Apple's flagship platform of

7808-465: The Lisa only had the original seven applications that Apple had deemed enough to "do everything". UniPress Software released UNIX System III for $ 495 (equivalent to $ 1,500 in 2023). Santa Cruz Operation (SCO) published Microsoft Xenix (version 3), a Unix-like command-line operating system for the Lisa 2, and Microsoft's Multiplan 2.1 spreadsheet for Xenix. Other Lisa Xenix apps include Quadratron's Q-Office suite. BYTE previewed

7930-495: The Lisa, as compared to the earlier Apple II ‍ — ‍ AST offered a 1.5  MB memory board which, when combined with the standard Apple 512  KB memory board, expanded the Lisa to a total of 2 MB of memory, the maximum amount that the MMU can address. Late in the product life of the Lisa, there were third-party hard disk drives, SCSI controllers , and double-sided 3.5-inch floppy-disk upgrades. Unlike

8052-400: The Macintosh, pixels were square, and a GrafPort had a default resolution of 72 pixels per inch, chosen to match conventions established by the printing industry of having 72 points per inch. QuickDraw also contained a number of scaling and mapping functions. QuickDraw maintained a number of global variables per process, chief among these being the current port. This originally simplified

8174-624: The QuickDraw name and were able to interoperate with QuickDraw PixMap and picture data structures, but were otherwise completely separate in functionality. With Mac OS X, QuickDraw became part of the Carbon API . In 2005, with the release of Mac OS X 10.4, QuickDraw was officially deprecated. In 2010 with MacPaint 1.3's source code release through the Computer History Museum , a historical version of QuickDraw source code became available too. Apple Lisa Lisa

8296-474: The Twiggy floppy drives in favor of a single 400K Sony microfloppy . The Lisa 2 has as little as 512 KB of RAM. The Lisa 2/5 consists of a Lisa 2 bundled with an external 5- or 10-megabyte hard drive. In 1984, at the same time the Macintosh was officially announced, Apple offered free upgrades to the Lisa 2/5 to all Lisa 1 owners, by replacing the pair of Twiggy drives with a single 3.5-inch drive, and updating

8418-707: The Workshop. The Lisa Office System is the GUI environment for end users. The Workshop is a program development environment and is almost entirely text-based, though it uses a GUI text editor. The Lisa Office System was eventually renamed 7/7 which refers to the seven supplied application programs: LisaWrite, LisaCalc, LisaDraw, LisaGraph, LisaProject , LisaList, and LisaTerminal. Apple's warranty said that this software works precisely as stated, and Apple refunded an unspecified number of users, in full, for their systems. These operating system frailties, and costly recalls, combined with

8540-518: The actual signal are coded separately. A number of lossless audio compression formats exist. See list of lossless codecs for a listing. Some formats are associated with a distinct system, such as Direct Stream Transfer , used in Super Audio CD and Meridian Lossless Packing , used in DVD-Audio , Dolby TrueHD , Blu-ray and HD DVD . Some audio file formats feature a combination of

8662-484: The ad hoc protected memory implementation, due to the lack of a Motorola memory management unit . Cost-cutting measures that target the consumer market, and the delayed availability of the 68000 processor and its impact on the design process, made the user experience sluggish. The workstation -tier high price and lack of a technical software application library made it a difficult sale for all markets. The IBM PC's popularity and Apple's decision to compete with itself through

8784-399: The advent of 32-Bit QuickDraw, such offscreen worlds had to be created and set up by hand by programmers within their applications. This could be error-prone, as it involved three or more separate and fairly complex data structures (CGrafPort, PixMap and GDevice, and for indexed devices, the color look-up table and its inverse). With 32-Bit QuickDraw, OS support for handling this was added, with

8906-403: The amount of data required to represent an image at the cost of a relatively small reduction in image quality and has become the most widely used image file format . Its highly efficient DCT-based compression algorithm was largely responsible for the wide proliferation of digital images and digital photos . Lempel–Ziv–Welch (LZW) is a lossless compression algorithm developed in 1984. It

9028-400: The associated GrafPort. A window's content area did not include the window's frame, drop shadow or title bar (if any). QuickDraw coordinates referred to the infinitely thin lines between pixel locations. An actual pixel was drawn in the space to the immediate right and below the coordinate. This made it easier for programmers to avoid graphical glitches caused by off-by-one errors . On

9150-440: The basic elements of what constituted a workable GUI. The Lisa team put a great deal of work into making the graphical interface a mainstream commercial product. The Lisa was a major project at Apple, which reportedly spent more than $ 50 million on its development. More than 90 people participated in the design, plus more in the sales and marketing effort, to launch the machine. BYTE magazine credited Wayne Rosing with being

9272-418: The basis for the modified discrete cosine transform (MDCT) used by modern audio compression formats such as MP3, Dolby Digital , and AAC. MDCT was proposed by J. P. Princen, A. W. Johnson and A. B. Bradley in 1987, following earlier work by Princen and Bradley in 1986. The world's first commercial broadcast automation audio compression system was developed by Oscar Bonello, an engineering professor at

9394-487: The better-known Huffman algorithm. It uses an internal memory state to avoid the need to perform a one-to-one mapping of individual input symbols to distinct representations that use an integer number of bits, and it clears out the internal memory only after encoding the entire string of data symbols. Arithmetic coding applies especially well to adaptive data compression tasks where the statistics vary and are context-dependent, as it can be easily coupled with an adaptive model of

9516-517: The black and white APIs were added. Initially, Color QuickDraw was only capable of operating with 1, 2, 4 and 8-bit video cards, which were all that was available at the time. Soon after however, 24-bit video cards appeared (so-called true color), and QuickDraw was updated again to support up to 32 bits per pixel (in reality, 24 bits, with 8 unused) of color data ("32-Bit QuickDraw"). The architecture always allowed for this, however, so no new APIs were necessary. The color data structures themselves allowed

9638-461: The boot ROM and I/O ROM. In addition, the Lisa 2's new front faceplate accommodates the reconfigured floppy disk drive, and it includes the new inlaid Apple logo and the first Snow White design language elements. The Lisa 2/10 has a 10 MB internal hard drive, no parallel port, and a standard configuration of 1 MB of RAM. Developing early Macintosh software required a Lisa   2. There were relatively few third-party hardware offerings for

9760-410: The coding algorithm can be critical; for example, when there is a two-way transmission of data, such as with a telephone conversation, significant delays may seriously degrade the perceived quality. In contrast to the speed of compression, which is proportional to the number of operations required by the algorithm, here latency refers to the number of samples that must be analyzed before a block of audio

9882-660: The core information of the original data while significantly decreasing the required storage space. Large language models (LLMs) are also capable of lossless data compression, as demonstrated by DeepMind 's research with the Chinchilla 70B model. Developed by DeepMind, Chinchilla 70B effectively compressed data, outperforming conventional methods such as Portable Network Graphics (PNG) for images and Free Lossless Audio Codec (FLAC) for audio. It achieved compression of image and audio data to 43.4% and 16.4% of their original sizes, respectively. Data compression can be viewed as

10004-402: The creation of GrafPorts and their associated BitMaps or PixMaps "offscreen", where graphics could be composed in memory without it being visible immediately on the screen. Pixels could be transferred between these offscreen ports and the screen using the QuickDraw blitting function CopyBits. Such offscreen compositing is the workhorse for games and graphics-intensive applications. However, until

10126-467: The data in question. For example, the human eye is more sensitive to subtle variations in luminance than it is to the variations in color. JPEG image compression works in part by rounding off nonessential bits of information. A number of popular compression formats exploit these perceptual differences, including psychoacoustics for sound, and psychovisuals for images and video. Most forms of lossy compression are based on transform coding , especially

10248-462: The data must be decompressed as the data flows, rather than after the entire data stream has been transmitted. Not all audio codecs can be used for streaming applications. Latency is introduced by the methods used to encode and decode the data. Some codecs will analyze a longer segment, called a frame , of the data to optimize efficiency, and then code it in a manner that requires a larger segment of data at one time to decode. The inherent latency of

10370-414: The display resolution. A raster system requires much less processing power however, and was the prevailing paradigm at the time that QuickDraw was developed. QuickDraw defined a key data structure, the graphics port , or GrafPort. This was a logical drawing area where graphics could be drawn. The most obvious on-screen "object" corresponding to a GrafPort was a window , but the entire desktop view could be

10492-417: The encoding and decoding. The design of data compression schemes involves balancing the degree of compression, the amount of distortion introduced (when using lossy data compression ), and the computational resources or time required to compress and decompress the data. Lossless data compression algorithms usually exploit statistical redundancy to represent data without losing any information , so that

10614-469: The file size is reduced to 5-20% of the original size and a megabyte can store about a minute's worth of music at adequate quality. Several proprietary lossy compression algorithms have been developed that provide higher quality audio performance by using a combination of lossless and lossy algorithms with adaptive bit rates and lower compression ratios. Examples include aptX , LDAC , LHDC , MQA and SCL6 . To determine what information in an audio signal

10736-465: The firm that eventually became IDEO. Bruce Daniels was in charge of applications development, and Larry Tesler was in charge of system software. The user interface was designed in six months, after which the hardware, operating system, and applications were all created in parallel. In 1982, Steve Jobs was forced out of the Lisa project, and he appropriated Jef Raskin 's existing Macintosh project. Raskin had conceived and led Macintosh since 1979 as

10858-472: The help of Sun Remarketing, Apple disposed of approximately 2,700 unsold Lisa units in a guarded landfill in Logan, Utah , to receive a tax write-off on the unsold inventory. Some leftover Lisa computers and spare parts were available until Cherokee Data (which purchased Sun Remarketing) went out of business. The Lisa was first introduced on January 19, 1983. It is one of the first personal computer systems with

10980-455: The late 1980s, digital images became more common, and standards for lossless image compression emerged. In the early 1990s, lossy compression methods began to be widely used. In these schemes, some loss of information is accepted as dropping nonessential detail can save storage space. There is a corresponding trade-off between preserving information and reducing size. Lossy data compression schemes are designed by research on how people perceive

11102-603: The lower-priced Macintosh also hindered Lisa's acceptance. In 1982, after Steve Jobs was forced out of the Lisa project by Apple's board of directors, he appropriated the Macintosh project from Jef Raskin , who had conceived it as a sub- $ 1,000 (equivalent to $ 4,200 in 2023) text-based appliance computer in 1979. Jobs immediately redefined Macintosh to be graphical, but as a less expensive and more focused alternative to Lisa. Macintosh's launch in January 1984 quickly surpassed Lisa's underwhelming sales. Jobs began assimilating increasing numbers of Lisa staff, as he had done with

11224-412: The mechanism is outlined in the patent. Regions are implemented using both vertical and horizontal compression . A region is stored as a series of horizontal scan lines (" rasters "), each of which contains a vertical coordinate followed by a list of horizontal inversion coordinates. Each inversion point can be thought of as toggling inclusion in the region for all the points after it: the first point turns

11346-543: The most important person in the development of the computer's hardware until the machine went into production, at which point he became the technical lead for the entire Lisa project. The hardware development team was headed by Robert Paratore. The industrial design, product design, and mechanical packaging were headed by Bill Dresselhaus, the Principal Product Designer of Lisa, with his team of internal product designers and contract product designers from

11468-507: The most popular algorithms for lossless storage. DEFLATE is a variation on LZ optimized for decompression speed and compression ratio, but compression can be slow. In the mid-1980s, following work by Terry Welch , the Lempel–Ziv–Welch (LZW) algorithm rapidly became the method of choice for most general-purpose compression systems. LZW is used in GIF images, programs such as PKZIP , and hardware devices such as modems. LZ methods use

11590-536: The much less expensive Mac. The Macintosh project assimilated a lot more Lisa staff. The final revision, the Lisa 2/10, was modified and sold as the Macintosh XL . The high cost and the delays in its release date contributed to the Lisa's discontinuation although it was repackaged and sold at $ 4,995 , as the Lisa 2. In 1986, the entire Lisa platform was discontinued. In 1987, Sun Remarketing purchased about 5,000 Macintosh XLs and upgraded them. In 1989, with

11712-441: The name was an acronym for "Local Integrated Software Architecture". Because Steve Jobs's first daughter was named Lisa (born in 1978), it was sometimes inferred that the name also had a personal association, and perhaps that the acronym was a backronym contrived later to fit the name. Andy Hertzfeld said that the acronym was reverse-engineered from the name "Lisa" in late 1982 by the Apple marketing team after they had hired

11834-405: The new video architecture virtually seamless to both developers and end users. Color QuickDraw introduced new data structures, including GDevices to represent each attached video card/monitor, and a new color GrafPort (CGrafPort) structure to handle color, as well as PixMaps instead of BitMaps for multiple bits-per-pixel images. One of the hacks for compatibility used here was that the new structure

11956-477: The next several decades. The column-based interface , for instance, utilized by Mac OS X, had originally been developed for Lisa. It had been discarded in favor of the icon view. Apple's culture of object-oriented programming on Lisa contributed to the 1988 conception of Pink , the first attempt to re-architect the operating system of Macintosh. In 1989, after Wayne Rosing had moved to Sun Microsystems , he reflected on his time at Apple, recalling that building

12078-429: The original Macintosh, the Lisa has expansion slots. The Lisa 2 motherboard has a very basic backplane with virtually no electronic components, but plenty of edge connector sockets and slots. There are two RAM slots, one CPU upgrade slot, and one I/O slot, all in parallel. At the other end are three Lisa slots in parallel. In January 1985, following the Macintosh, the Lisa 2/10 (with integrated 10 MB hard drive)

12200-482: The picture may be placed at new coordinates or scaled without the loss of resolution commonly encountered in bitmap scaling. A picture can be saved to disk in which form it defines the Apple PICT format. An entire BitMap (or PixMap, when referring to color images) may be copied from one GrafPort to another, with scaling and clipping. Known as blitting , or CopyBits , after the name of the function, this operation

12322-448: The press was full of intentionally-leaked rumors about a fall release of a 'baby Lisa' that would work in much the same way, only faster and cheaper. Its name: Macintosh." Lisa was launched on January 19, 1983. Its low sales were quickly surpassed by the January 1984 launch of the Macintosh. Newer versions of the Lisa were introduced that addressed its faults and lowered its price considerably, but it failed to achieve sales comparable to

12444-473: The principles of simultaneous masking —the phenomenon wherein a signal is masked by another signal separated by frequency—and, in some cases, temporal masking —where a signal is masked by another signal separated by time. Equal-loudness contours may also be used to weigh the perceptual importance of components. Models of the human ear-brain combination incorporating such effects are often called psychoacoustic models . Other types of lossy compressors, such as

12566-472: The process is reversible. Lossless compression is possible because most real-world data exhibits statistical redundancy. For example, an image may have areas of color that do not change over several pixels; instead of coding "red pixel, red pixel, ..." the data may be encoded as "279 red pixels". This is a basic example of run-length encoding ; there are many schemes to reduce file size by eliminating redundancy. The Lempel–Ziv (LZ) compression methods are among

12688-401: The project evolved into the " window-and-mouse-driven " form of its eventual release. Trip Hawkins and Jef Raskin contributed to this change in design. Apple's co-founder Steve Jobs was involved in the concept. At Xerox's Palo Alto Research Center (PARC), research had already been underway for several years to create a new humanized way to organize the computer screen, which became known as

12810-752: The region on, the second turns it off, and so on. Further compression is achieved by storing each line differentially: each line contains only the differences from the previous line rather than a full set of inversion points. Finally, identical adjacent scan lines are efficiently encoded by simply skipping them. In this way, a commonly used region, the rounded corner rectangle, is efficiently encoded, and complex operations such as region composition and image clipping may be done without requiring either extensive processor cycles or large amounts of memory. (The original systems executing QuickDraw code used processors operating at 8 megahertz clock rates and systems had but 128 kilobytes of writable memory.) Because regions are bound to

12932-452: The region, drawing various QuickDraw shapes, and closing the region. Hidden routines construct the region as the QuickDraw commands are executed. Bitmaps may also be converted to regions, and bitmaps may be made from regions by "painting" or "filling" the region into a graphics port. The internal structure of a region, other than the storage length and its bounding rectangle, is opaque - there are no Apple-published documents available, though

13054-488: The same time as louder sounds. Those irrelevant sounds are coded with decreased accuracy or not at all. Due to the nature of lossy algorithms, audio quality suffers a digital generation loss when a file is decompressed and recompressed. This makes lossy compression unsuitable for storing the intermediate results in professional audio engineering applications, such as sound editing and multitrack recording. However, lossy formats such as MP3 are very popular with end-users as

13176-546: The size of data files, enhancing storage efficiency and speeding up data transmission. K-means clustering, an unsupervised machine learning algorithm, is employed to partition a dataset into a specified number of clusters, k, each represented by the centroid of its points. This process condenses extensive datasets into a more compact set of representative points. Particularly beneficial in image and signal processing , k-means clustering aids in data reduction by replacing groups of data points with their centroids, thereby preserving

13298-595: The space required to store or transmit them. The acceptable trade-off between loss of audio quality and transmission or storage size depends upon the application. For example, one 640 MB compact disc (CD) holds approximately one hour of uncompressed high fidelity music, less than 2 hours of music compressed losslessly, or 7 hours of music compressed in the MP3 format at a medium bit rate . A digital sound recorder can typically store around 200 hours of clearly intelligible speech in 640 MB. Lossless audio compression produces

13420-489: The storage and processor cycles available to the operation, and the complexity of the algorithm.) Apple has recently (in the Carbon API ) defined regions as an opaque structure under some program compilation options. Any series of graphics calls to QuickDraw can be recorded in a structure called a Picture . This can then be saved in memory and "played back" at any time, reproducing the graphics sequence. At playback time

13542-452: The supplier, hiring specially trained personnel, or at least, a much steeper learning curve to maintain and operate. Earlier GUI-controlled personal computers were not mass-marketed; for example, Xerox PARC manufactured its Alto workstation only for Xerox and select partners from the early to mid-1970s. Development of project "LISA" began in 1978. It underwent many changes and shipped at US$ 9,995 (equivalent to $ 30,600 in 2023) with

13664-511: The symbol that compresses best, given the previous history). This equivalence has been used as a justification for using data compression as a benchmark for "general intelligence". An alternative view can show compression algorithms implicitly map strings into implicit feature space vectors , and compression-based similarity measures compute similarity within these feature spaces. For each compressor C(.) we define an associated vector space ℵ, such that C(.) maps an input string x, corresponding to

13786-478: The topic in the late 1940s and early 1950s. Other topics associated with compression include coding theory and statistical inference . There is a close connection between machine learning and compression. A system that predicts the posterior probabilities of a sequence given its entire history can be used for optimal data compression (by using arithmetic coding on the output distribution). Conversely, an optimal compressor can be used for prediction (by finding

13908-509: The vector norm ||~x||. An exhaustive examination of the feature spaces underlying all compression algorithms is precluded by space; instead, feature vectors chooses to examine three representative lossless compression methods, LZW, LZ77, and PPM. According to AIXI theory, a connection more directly explained in Hutter Prize , the best possible compression of x is the smallest possible software that generates x. For example, in that model,

14030-715: The very high price point, led to the failure of the Lisa in the marketplace. NASA purchased Lisa machines, mainly to use the LisaProject program. In 2018, the Computer History Museum announced it would be releasing the source code for Lisa OS, following a check by Apple to ensure this would not impact other intellectual property. For copyright reasons, this release does not include the American Heritage dictionary. For its 40th anniversary on January 19, 2023, Lisa OS Software version 3.1's source code

14152-609: Was developed in 1950. Transform coding dates back to the late 1960s, with the introduction of fast Fourier transform (FFT) coding in 1968 and the Hadamard transform in 1969. An important image compression technique is the discrete cosine transform (DCT), a technique developed in the early 1970s. DCT is the basis for JPEG, a lossy compression format which was introduced by the Joint Photographic Experts Group (JPEG) in 1992. JPEG greatly reduces

14274-554: Was exactly the same size as the old one, with most data members in the same place, but with additional handles and pointers to color structures in place of the BitMap fields. The upper two bits of the rowBytes field were pressed into use as flags to distinguish a GrafPort from a CGrafPort (they were always zero on old-style GrafPorts because a BitMap could never feasibly be so wide as to ever set these bits). The use of these two high bits would come back to haunt QuickDraw later, as it forced

14396-425: Was introduced by P. Cummiskey, Nikil S. Jayant and James L. Flanagan . Perceptual coding was first used for speech coding compression, with linear predictive coding (LPC). Initial concepts for LPC date back to the work of Fumitada Itakura ( Nagoya University ) and Shuzo Saito ( Nippon Telegraph and Telephone ) in 1966. During the 1970s, Bishnu S. Atal and Manfred R. Schroeder at Bell Labs developed

14518-538: Was named for my daughter." The project began in 1978 as an effort to create a more modern version of the then-conventional design epitomized by the Apple II . A ten-person team occupied its first dedicated office at 20863 Stevens Creek Boulevard next to the Good Earth restaurant, and nicknamed "the Good Earth building". Initial team leader Ken Rothmuller was soon replaced by John Couch , under whose direction

14640-435: Was re-branded MacWorks XL as the primary system application, to convert the Lisa into the Macintosh XL . The launch version of Lisa Office System can not be used for programming, requiring the separate development OS called Lisa Workshop to be toggled and booted. Lisa Workshop was also used to develop Macintosh software for its first few years, until a Macintosh-native development system was released. For most of its lifetime,

14762-497: Was rebranded as Macintosh XL. It was given a hardware and software kit, enabling it to reboot into Macintosh mode and positioning it as the high-end Macintosh. The price was lowered yet again, to $ 4,000, and sales tripled, but CEO John Sculley said that Apple would have lost money increasing production to meet the new demand. Apple discontinued the Macintosh XL, leaving an eight-month void in Apple's high-end product line until

14884-470: Was related to its previous value and the color of the object being drawn. The set of attributes of the pen and text drawing are associated with the GrafPort. Regions are a key data structure in QuickDraw. They define an arbitrary set of pixels, rather like a bitmap, but in a compressed form which can be very rapidly manipulated in complex ways. Regions can be combined (union), subtracted (difference), and XORed to form other Regions. They can be used within

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