The Image codecs is a method of compression/decompression of image files or image data. The codecs stands for Coders / Decoders.
There are various kinds of image codecs available. Since these codecs have been implemented by different algorithms by number of companies; they have different specification and application in various fields.
The various software image codecs are:
- JPEG 2000
- Good photo quality.
- Bitmap files (bmp) may be easily created from existing pixel data stored in an array in memory. Pixel values may be modified individually or as large groups by altering a palette if present.
- Bitmap codecs may translate well to dot-format output devices such as CRTs and printers.
- Bmp codecs are Limited to RGB-images.
- These codecs generally does not support effective image compression. They can be very large, particularly if the image contains a large number of colors.
- It’s also not supported well across multiple platforms.
- Shrinking this image codecs by decimation (throwing away pixels) can change the image in an unacceptable manner.
- This codecs allows you to create transparent, interlaced, and animated graphics for the Web
- Compresses by scanning horizontally across a row of pixels and finding solid areas of color. Indexes the pixels based on the 256 color palette in the file. No image information is lost.
- The only graphic file format (codec) that is universally supported by all graphical browsers, regardless of version. Most popular and versatile format for distributing color image on the Web.
- This codec is not good for photographic images due to its limited number of colors generally 256 colors.
- JPEG codec has low complexity. Picture quality is generally good enough.
- This is also memory efficient. i.e. good compression allows to reduce the file size.
- It works very well for “slide-show” movies that have a very low frame rate.
- Also it has reasonable coding efficiency
- Single Resolution & Single Quality
- No target bit rate
- Blocking artifacts at low bit rate
- No lossless capability
- Poor error resilience
- No tiling & No regions of interest
- Improved coding efficiency
- Full quality scalability
- From lossless to lossy at different bit rate
- Spatial scalability
- Improved error resilience compared to jpeg
- Tiling & Region of interests
- Requires more in memory compared to JPEG.
- Requires more computation time
- MJPEG codecs are often used as storage formats for large files that need to be archived with good quality. It is a lossy codec, but at 100% quality, the image degradation is minimal.
- At WWW data rates (5-20K), JPEG may produce better results than Cinepak.
- All the JPEG codecs require significant amounts of CPU power and are not well suited to video playback at CD-ROM or higher data rates, except when assisted by a hardware capture card.
- Large image and/or high frame rate movies usually don’t play smoothly.
- Compared to a JPEG, an uncompressed TIFF codec retains the best quality of a photographic image, making it ideal for digital masters (preservation) and print documents.
- Low or high-resolution images codec of photographic quality (images containing many colors that blend and fade). Encoding scheme is Lossless; files can be compressed or uncompressed.
- Codecs produce large file size
- A better compression than GIF codec, which only scans rows. The compression is ‘lossless’, you do not lose color information as you compress the file smaller. Typically compresses images 5-25% better than GIF.
- It is a best one for creating complex live transparency, high-color graphics, and better compressed low-color graphics.
- Designed to be network-friendly, so it is recognized and supported on all platforms.
- It doesn’t support animation
- It does not use predictive frames
- It has lower quality than PICT or TIFF
To commercialize these image codecs couples of portals are available where you can compare and procure them. Such portals are design-reuse, chipestimates, IPsupermarket.com which allows you to buy/sell or license these image codecs.