Inside Macintosh: QuickTime Components

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Format of Compressed Data and Files

The formatFlags field of the compressor information structure contains a number of flags that define the possible format of compressed data produced by the component and the format of compressed files that the component can handle during decompression. The defined flags are as follows:

#define codecInfoDepth1             (1L<<0)     /* compressed images with 1-bit color
                                                    depth available */
#define codecInfoDepth2             (1L<<1)     /* compressed images with 2-bit color
                                                    depth available */
#define codecInfoDepth4             (1L<<2)     /* compressed images with 4-bit color
                                                    depth available */
#define codecInfoDepth8             (1L<<3)     /* compressed images with 8-bit color
                                                    depth available */
#define codecInfoDepth16            (1L<<4)     /* compressed images with 16-bit color
                                                    depth available */
#define codecInfoDepth32            (1L<<5)     /* compressed images with 32-bit color
                                                    depth available */
#define codecInfoDepth24            (1L<<6)     /* compressed images with 24-bit color
                                                    depth available */
#define codecInfoDepth33            (1L<<7)     /* compressed data with monochrome images
                                                    of 1-bit color depth */
#define codecInfoDepth34            (1L<<8)     /* compressed images with 2-bit grayscale
                                                    depth available */
#define codecInfoDepth36            (1L<<9)     /* compressed images with 4-bit grayscale
                                                    depth available */
#define codecInfoDepth40            (1L<<10)    /* compressed images with 8-bit grayscale
                                                    depth available */
#define codecInfoStoresClut(1L<<11)             /* compressed data with custom color
                                                    tables */
#define  codecInfoDoesLossless
                                    (1L<<12)    /* compressed data stored lossless
                                                    format */
#define codecInfoSequenceSensitive
                                    (1L<<13) /* compressed data requires non-key
                                                    frames to be decompressed in same
                                                    order as compressed */

Flag descriptions

codecInfoDepth1
Indicates whether the component can work with files containing color images with a color depth of 1 bit. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth2
Indicates whether the component can work with files containing color images with a color depth of 2 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth4
Indicates whether the component can work with files containing color images with a color depth of 4 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth8
Indicates whether the component can work with files containing color images with a color depth of 8 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth16
Indicates whether the component can work with files containing color images with a color depth of 16 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth32
Indicates whether the component can work with files containing color images with a color depth of 32 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files. This flag is the same as the codecInfoDepth24 flag except it contains one extra byte used as an alpha channel.
codecInfoDepth24
Indicates whether the component can work with files containing color images with a color depth of 24 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth33
Indicates whether the component can work with files containing monochrome images, which have a grayscale depth of 1 bit. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth34
Indicates whether the component can work with files containing grayscale images with a grayscale depth of 2 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth36
Indicates whether the component can work with files containing grayscale images with a grayscale depth of 4 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoDepth40
Indicates whether the component can work with files containing grayscale images with a grayscale depth of 8 bits. If this flag is set to 1, the component can compress into and decompress from files at this depth. If this flag is set to 0, the component cannot handle such files.
codecInfoStoresClut
Indicates whether the component can accommodate compressed data with custom color tables. If this flag is set to 1, the component can create compressed files with custom color tables and can decompress files that contain custom color tables. If this flag is set to 0, the component cannot handle such files.
codecInfoDoesLossless
Indicates whether the component can perform lossless compression or decompression operations. Lossless compression results in a decompressed image that is exactly the same as the original, uncompressed image. If this flag is set to 1, the component can perform lossless compression or decompression. If this flag is set to 0, the component cannot perform lossless operations. The application specifies a lossless operation by setting the desired quality level to codecLosslessQuality (see Inside Macintosh: QuickTime for more information about quality levels).
codecInfoSequenceSensitive
Indicates that the compressed data generated by this image compressor component has the requirement that non-key frames in a sequence be decompressed in the same order that they were compressed.
© 1997 Apple Computer, Inc.

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