the number is 1337 speak for the letters IDCT MCo (motion compensation) */
struct xvmc_pix_fmt {
-/** Set by the calling application.
- Once set these values are not supposed to be modified.
-*/
-//@{
/** The field contains the special constant value AV_XVMC_ID.
It is used as a test that the application correctly uses the API,
and that there is no corruption caused by pixel routines.
*/
int xvmc_id;
- /** Pointer to the block array allocated by XvMCCreateBlocks()
- it contains differential pixel data (in MoCo mode)
- or coefficients for IDCT.
- - application - set during initialization
- - libavcodec - unchanged
+ /** Pointer to the block array allocated by XvMCCreateBlocks().
+ The array has to be freed by XvMCDestroyBlocks().
+ Each group of 64 values represents one data block of differential
+ pixel information (in MoCo mode) or coefficients for IDCT.
+ - application - set the pointer during initialization
+ - libavcodec - fills coefficients/pixel data into the array
*/
short* data_blocks;
/** Pointer to the macroblock description array allocated by
- XvMCCreateMacroBlocks().
- - application - set during initialization
- - libavcodec - unchanged
+ XvMCCreateMacroBlocks() and freed by XvMCDestroyMacroBlocks().
+ - application - set the pointer during initialization
+ - libavcodec - fills description data into the array
*/
XvMCMacroBlock* mv_blocks;
- application - set during initialization
- libavcodec - unchanged
*/
- int total_number_of_mv_blocks;
+ int allocated_mv_blocks;
/** Number of blocks that can be stored at once in the data_blocks array.
- application - set during initialization
- libavcodec - unchanged
*/
- int total_number_of_data_blocks;
+ int allocated_data_blocks;
- /** Indicates that the hardware would interpret data_blocks as IDCT
+ /** Indicate that the hardware would interpret data_blocks as IDCT
coefficients and perform IDCT on them.
- application - set during initialization
- libavcodec - unchanged
int unsigned_intra;
/** Pointer to the surface allocated by XvMCCreateSurface().
+ It has to be freed by XvMCDestroySurface() on application exit.
It identifies the frame and its state on the video hardware.
- application - set during initialization
- libavcodec - unchanged
*/
XvMCSurface* p_surface;
-//}@
/** Set by the decoder before calling ff_draw_horiz_band(),
needed by the XvMCRenderSurface function. */
unsigned int flags;
//}@
- /** Offset in the mv array for the current slice.
- Macroblocks described before that offset are assumed to have already
- been passed to the hardware.
+ /** Number of macroblock descriptions in the mv_blocks array
+ that have already been passed to the hardware.
- application - zeroes it on get_buffer().
A successful ff_draw_horiz_band() may increment it
with filled_mb_block_num or zero both.
*/
int start_mv_blocks_num;
- /** Number of mv blocks that are filled by libavcodec and have to be
+ /** Number of new macroblock descriptions in the mv_blocks array (after
+ start_mv_blocks_num) that are filled by libavcodec and have to be
passed to the hardware.
- application - zeroes it on get_buffer() or after successful
ff_draw_horiz_band().
*/
int filled_mv_blocks_num;
- /** Offset to the next free data block. The mv_blocks hold a number
- pointing to the data blocks.
- - application - zeroes it on get_buffer() and after successful
- ff_draw_horiz_band().
- - libavcodec - each macroblock increases it with the number
+ /** Number of the the next free data block; one data block consists of
+ 64 short values in the data_blocks array.
+ All blocks before this one have already been claimed by placing their
+ position into the corresponding block description structure field,
+ that are part of the mv_blocks array.
+ - application - zeroes it on get_buffer().
+ A successful ff_draw_horiz_band() may zero it together
+ with start_mb_blocks_num.
+ - libavcodec - each decoded macroblock increases it by the number
of coded blocks it contains.
*/
int next_free_data_block_num;
/** extensions may be placed here */
#if LIBAVCODEC_VERSION_MAJOR < 53
//@{
- /** State - used to work around limitations in the MPlayer video system.
+ /** State flags used to work around limitations in the MPlayer video system.
0 - Surface is not used.
1 - Surface is still held in application to be displayed or is
still visible.