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- Indeo® Video 4 Release Notes, June 28, 1996
-
- Introduction
-
-
- This version of the codec introduces a number
- of benefits including performance improvements, quality enhancements,
- and interactive features. The latest version of the Indeo
- video 4 codec, along with documentation, sample source
- code, the latest technical information updates, and access to
- technical support are available on the Indeo software website at http://developer.intel.com/ial/indeo/
-
- Performance Improvements
-
-
- The performance of this codec has been enhanced
- in several ways:
-
- -The codec has been optimized for MMX technology.
- MMX technology is a major enhancement to the Intel Architecture
- that will make mainstream PCs richer multimedia and communications
- platforms. This enhancement includes 57 new instructions that
- will allow Intel processors to deliver better performance for
- multimedia and communications computation.
-
- -The codec uses less memory. The actual amount
- of memory used by the codec when playing a given file will vary
- depending on how that file was compressed, but the new codec will
- use anywhere from 25% to 40% less memory to open and play a file
- than the previous version.
-
- -Files load and start playing faster. The actual
- time it takes to open and begin playing a file on a given PC will
- vary based on system performance features such as CPU speed, RAM,
- L2 cache, etc., but on average the new codec will open and start
- playing files 20% to 40% faster than the previous version.
-
- -Playback performance has improved. A number
- of optimizations have been made to speed up playback of video
- files, especially in 16-bit (65,000-color) display mode.
-
- Compression Enhancements
-
-
- Enhancements have been made to the offline encoder,
- and a new compression mode called the Quick Compressor has been
- added to make compressing video files much faster and easier.
-
- Online Help
-
- An online help menu is now available in the encoder's
- Configure dialog. This will help guide the user through the various
- options available for encoding video clips.
-
- Offline Encoder Improvements
-
-
- Improvements have been made to the offline encoder
- that will allow compressed video clips to display better quality
- at lower data rates. This will be especially noticeable in clips
- compressed at single-speed CD-ROM data rates (~ 100-135 Kbytes/second)
- and lower, and in clips compressed at 30 frames/second at double-speed
- CD-ROM data rates (~ 200-250 Kbytes/second) and below. You must
- compress clips with the new version of the codec to see these
- improvements.
-
- The Quick Compressor
-
- Normal offline encoding can be time-consuming. The
- new Quick Compress option allows Indeo video interactive to encode
- video many times faster than it otherwise would. Exactly how
- much faster depends on the specific content of the source video
- and the other encoder options you've selected. The compression
- speed improvement, however, is significant: compression jobs
- that once took hours may now compress in just minutes.
-
- One reason the Quick Compressor is so much faster
- than the offline compressor is that it uses a subset of the offline
- encoder's compression techniques. This speeds compression but
- slightly reduces overall visual quality. The Quick Compressor
- is also slightly less accurate at maintaining the requested target
- data rate than the offline encoder.
-
- If you choose Quick Compress several other options
- are automatically disabled: bidirectional prediction, transparency,
- quality, and minimum viewport size (local decode). Also, the
- Quick Compressor can encode video at resolutions up to 640 x 480,
- whereas the offline encoder supports resolutions up to 8192 x
- 8192.
-
- The Quick Compressor is extremely useful for tasks
- such as previewing edits and special effects, and for prototyping
- multimedia applications. It can also save time when creating
- video for hard disk applications, where data rate control is less
- critical. However, after you've previewed the video and made
- any required adjustments, it's best to use the off-line encoder
- to compress the video for your final product. For the best quality
- at lower data rates, or to achieve a steady data rate without
- spikes, do not use the Quick Compressor.
-
- The Indeo video 4 codec can play back any
- video clip compressed with the Quick Compressor.
-
- To enable quick compression, check the Quick Compress
- box in the Encoder Controls area of the encoder's Configure dialog
- box.
-
- Playback Enhancements
-
- The new version of Indeo video 4 offers
- enhanced playback quality, and new features designed to enhance
- the interactivity and video quality of Indeo video in multimedia
- applications.
-
- Playback Quality Improvements
-
- Changes have been made to the decoder which will
- improve the playback quality of both new and existing video clips:
-
- -A problem which was causing a pinkish color
- shift in both 16-bit (65,000-color) and 24-bit (16.7-million color)
- display modes has been eliminated.
-
- -Zoom-by-two quality has been improved in 16-bit
- (65,000-color) display mode. A problem which was causing an excessive
- dither pattern has been eliminated.
-
-
- Alternate Line Zoom-by-two
-
- Indeo video 4 supports alternate line zoom-by-two,
- a feature that doubles the video window size by horizontal pixel
- doubling and then drawing a row of black pixels in between each
- row of image data. This can help reduce some of the "jaggies"
- caused by vertical pixel doubling.
-
- Programming Interface Enhancements
-
- A number of enhancements have been made to the ICM
- programming interface. These changes will give developers creating
- multimedia playback applications improved control over the codec's
- interactive features, especially transparency and playback scalability.
-
- Custom Palettes and Dither Patterns
-
- A number of enhancements have been added to the codec
- to support the use of custom colors and dither patterns when playing
- video back in 8-bit (256-color) mode. Tools, documentation, and
- sample code supporting these new enhancements will be available
- shortly on the Indeo video home page.
-
- Installation Notes
-
- The current version of the setup program installs
- only the 32-bit version of the Indeo video 4 codec,
- on Microsoft* Windows* 95 and Windows NT* machines.