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Diffstat (limited to 'chromium/third_party/libvpx/source/libvpx/examples/simple_decoder.txt')
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diff --git a/chromium/third_party/libvpx/source/libvpx/examples/simple_decoder.txt b/chromium/third_party/libvpx/source/libvpx/examples/simple_decoder.txt deleted file mode 100644 index 90d9a6870e4..00000000000 --- a/chromium/third_party/libvpx/source/libvpx/examples/simple_decoder.txt +++ /dev/null @@ -1,96 +0,0 @@ -@TEMPLATE decoder_tmpl.c -Simple Decoder -============== -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ INTRODUCTION -This is an example of a simple decoder loop. It takes an input file -containing the compressed data (in IVF format), passes it through the -decoder, and writes the decompressed frames to disk. Other decoder -examples build upon this one. - -The details of the IVF format have been elided from this example for -simplicity of presentation, as IVF files will not generally be used by -your application. In general, an IVF file consists of a file header, -followed by a variable number of frames. Each frame consists of a frame -header followed by a variable length payload. The length of the payload -is specified in the first four bytes of the frame header. The payload is -the raw compressed data. -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ INTRODUCTION - - -Standard Includes ------------------ -For decoders, you only have to include `vpx_decoder.h` and then any -header files for the specific codecs you use. In this case, we're using -vp8. The `VPX_CODEC_DISABLE_COMPAT` macro can be defined to ensure -strict compliance with the latest SDK by disabling some backwards -compatibility features. Defining this macro is encouraged. -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DEC_INCLUDES -@DEFAULT -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DEC_INCLUDES - - -Initializing The Codec ----------------------- -The decoder is initialized by the following code. This is an example for -the VP8 decoder, but the code is analogous for all algorithms. Replace -`vpx_codec_vp8_dx()` with a pointer to the interface exposed by the -algorithm you want to use. The `cfg` argument is left as NULL in this -example, because we want the algorithm to determine the stream -configuration (width/height) and allocate memory automatically. This -parameter is generally only used if you need to preallocate memory, -particularly in External Memory Allocation mode. -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DEC_INIT -@DEFAULT -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DEC_INIT - - -Decoding A Frame ----------------- -Once the frame has been read into memory, it is decoded using the -`vpx_codec_decode` function. The call takes a pointer to the data -(`frame`) and the length of the data (`frame_sz`). No application data -is associated with the frame in this example, so the `user_priv` -parameter is NULL. The `deadline` parameter is left at zero for this -example. This parameter is generally only used when doing adaptive -postprocessing. -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DECODE -@DEFAULT -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DECODE - -Codecs may produce a variable number of output frames for every call to -`vpx_codec_decode`. These frames are retrieved by the -`vpx_codec_get_frame` iterator function. The iterator variable `iter` is -initialized to NULL each time `vpx_codec_decode` is called. -`vpx_codec_get_frame` is called in a loop, returning a pointer to a -decoded image or NULL to indicate the end of list. -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ GET_FRAME -@DEFAULT -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ GET_FRAME - - -Processing The Decoded Data ---------------------------- -In this example, we simply write the encoded data to disk. It is -important to honor the image's `stride` values. -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PROCESS_DX -@DEFAULT -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PROCESS_DX - - -Cleanup -------- -The `vpx_codec_destroy` call frees any memory allocated by the codec. -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DESTROY -@DEFAULT -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DESTROY - - -Error Handling --------------- -This example does not special case any error return codes. If there was -an error, a descriptive message is printed and the program exits. With -few exeptions, vpx_codec functions return an enumerated error status, -with the value `0` indicating success. -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DIE_CODEC -@DEFAULT -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DIE_CODEC |