Add more descriptions to the AVOption array taken from the avcodec.h AVCodec...

Add more descriptions to the AVOption array taken from the avcodec.h AVCodec structure member comments.

Originally committed as revision 7233 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/utils.c

@@ -464,7 +464,7 @@ static const AVOption options[]={
 {"extradata_size", NULL, OFFSET(extradata_size), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
 {"time_base", NULL, OFFSET(time_base), FF_OPT_TYPE_RATIONAL, DEFAULT, INT_MIN, INT_MAX},
 {"g", "set the group of picture size", OFFSET(gop_size), FF_OPT_TYPE_INT, 12, INT_MIN, INT_MAX, V|E},
-{"rate_emu", NULL, OFFSET(rate_emu), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
+{"rate_emu", "frame rate emulation", OFFSET(rate_emu), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
 {"ar", "set audio sampling rate (in Hz)", OFFSET(sample_rate), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
 {"ac", "set number of audio channels", OFFSET(channels), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX},
 {"cutoff", "set cutoff bandwidth", OFFSET(cutoff), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, A|E},
@@ -509,15 +509,15 @@ static const AVOption options[]={
 {"edge", "edge padding bug (autodetected per fourcc/version)", 0, FF_OPT_TYPE_CONST, FF_BUG_EDGE, INT_MIN, INT_MAX, V|D, "bug"},
 {"hpel_chroma", NULL, 0, FF_OPT_TYPE_CONST, FF_BUG_HPEL_CHROMA, INT_MIN, INT_MAX, V|D, "bug"},
 {"dc_clip", NULL, 0, FF_OPT_TYPE_CONST, FF_BUG_DC_CLIP, INT_MIN, INT_MAX, V|D, "bug"},
-{"ms", NULL, 0, FF_OPT_TYPE_CONST, FF_BUG_MS, INT_MIN, INT_MAX, V|D, "bug"},
+{"ms", "workaround various bugs in microsofts broken decoders", 0, FF_OPT_TYPE_CONST, FF_BUG_MS, INT_MIN, INT_MAX, V|D, "bug"},
 {"lelim", "single coefficient elimination threshold for luminance (negative values also consider dc coefficient)", OFFSET(luma_elim_threshold), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
 {"celim", "single coefficient elimination threshold for chrominance (negative values also consider dc coefficient)", OFFSET(chroma_elim_threshold), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
 {"strict", "how strictly to follow the standards", OFFSET(strict_std_compliance), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E, "strict"},
-{"very", NULL, 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_VERY_STRICT, INT_MIN, INT_MAX, V|E, "strict"},
-{"strict", NULL, 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_STRICT, INT_MIN, INT_MAX, V|E, "strict"},
+{"very", "strictly conform to a older more strict version of the spec or reference software", 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_VERY_STRICT, INT_MIN, INT_MAX, V|E, "strict"},
+{"strict", "strictly conform to all the things in the spec no matter what consequences", 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_STRICT, INT_MIN, INT_MAX, V|E, "strict"},
 {"normal", NULL, 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_NORMAL, INT_MIN, INT_MAX, V|E, "strict"},
-{"inofficial", NULL, 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_INOFFICIAL, INT_MIN, INT_MAX, V|E, "strict"},
-{"experimental", NULL, 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_EXPERIMENTAL, INT_MIN, INT_MAX, V|E, "strict"},
+{"inofficial", "allow inofficial extensions", 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_INOFFICIAL, INT_MIN, INT_MAX, V|E, "strict"},
+{"experimental", "allow non standarized experimental things", 0, FF_OPT_TYPE_CONST, FF_COMPLIANCE_EXPERIMENTAL, INT_MIN, INT_MAX, V|E, "strict"},
 {"b_qoffset", "qp offset between p and b frames", OFFSET(b_quant_offset), FF_OPT_TYPE_FLOAT, 1.25, FLT_MIN, FLT_MAX, V|E},
 {"er", "set error resilience strategy", OFFSET(error_resilience), FF_OPT_TYPE_INT, FF_ER_CAREFUL, INT_MIN, INT_MAX, V|D, "er"},
 {"careful", NULL, 0, FF_OPT_TYPE_CONST, FF_ER_CAREFUL, INT_MIN, INT_MAX, V|D, "er"},
@@ -582,7 +582,7 @@ static const AVOption options[]={
 {"left", NULL, 0, FF_OPT_TYPE_CONST, FF_PRED_LEFT, INT_MIN, INT_MAX, V|E, "pred"},
 {"plane", NULL, 0, FF_OPT_TYPE_CONST, FF_PRED_PLANE, INT_MIN, INT_MAX, V|E, "pred"},
 {"median", NULL, 0, FF_OPT_TYPE_CONST, FF_PRED_MEDIAN, INT_MIN, INT_MAX, V|E, "pred"},
-{"aspect", NULL, OFFSET(sample_aspect_ratio), FF_OPT_TYPE_RATIONAL, DEFAULT, 0, 10, V|E},
+{"aspect", "sample aspect ratio", OFFSET(sample_aspect_ratio), FF_OPT_TYPE_RATIONAL, DEFAULT, 0, 10, V|E},
 {"debug", "print specific debug info", OFFSET(debug), FF_OPT_TYPE_FLAGS, DEFAULT, 0, INT_MAX, V|A|S|E|D, "debug"},
 {"pict", "picture info", 0, FF_OPT_TYPE_CONST, FF_DEBUG_PICT_INFO, INT_MIN, INT_MAX, V|D, "debug"},
 {"rc", "rate control", 0, FF_OPT_TYPE_CONST, FF_DEBUG_RC, INT_MIN, INT_MAX, V|E, "debug"},
@@ -654,11 +654,11 @@ static const AVOption options[]={
 {"lmin", "min lagrange factor (VBR)", OFFSET(lmin), FF_OPT_TYPE_INT,  2*FF_QP2LAMBDA, 0, INT_MAX, V|E},
 {"lmax", "max lagrange factor (VBR)", OFFSET(lmax), FF_OPT_TYPE_INT, 31*FF_QP2LAMBDA, 0, INT_MAX, V|E},
 {"nr", "noise reduction", OFFSET(noise_reduction), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
-{"rc_init_occupancy", NULL, OFFSET(rc_initial_buffer_occupancy), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
+{"rc_init_occupancy", "number of bits which should be loaded into the rc buffer before decoding starts", OFFSET(rc_initial_buffer_occupancy), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
 {"inter_threshold", NULL, OFFSET(inter_threshold), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
 {"flags2", NULL, OFFSET(flags2), FF_OPT_TYPE_FLAGS, CODEC_FLAG2_FASTPSKIP, INT_MIN, INT_MAX, V|A|E|D, "flags2"},
 {"error", NULL, OFFSET(error_rate), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
-{"antialias", NULL, OFFSET(antialias_algo), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|D, "aa"},
+{"antialias", "MP3 antialias algorithm", OFFSET(antialias_algo), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|D, "aa"},
 {"auto", NULL, 0, FF_OPT_TYPE_CONST, FF_AA_AUTO, INT_MIN, INT_MAX, V|D, "aa"},
 {"fastint", NULL, 0, FF_OPT_TYPE_CONST, FF_AA_FASTINT, INT_MIN, INT_MAX, V|D, "aa"},
 {"int", NULL, 0, FF_OPT_TYPE_CONST, FF_AA_INT, INT_MIN, INT_MAX, V|D, "aa"},
@@ -669,8 +669,8 @@ static const AVOption options[]={
 {"mb_threshold", "macroblock threshold", OFFSET(mb_threshold), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
 {"dc", "intra_dc_precision", OFFSET(intra_dc_precision), FF_OPT_TYPE_INT, 0, INT_MIN, INT_MAX, V|E},
 {"nssew", "nsse weight", OFFSET(nsse_weight), FF_OPT_TYPE_INT, 8, INT_MIN, INT_MAX, V|E},
-{"skip_top", NULL, OFFSET(skip_top), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|D},
-{"skip_bottom", NULL, OFFSET(skip_bottom), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|D},
+{"skip_top", "number of macroblock rows at the top which are skipped", OFFSET(skip_top), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|D},
+{"skip_bottom", "number of macroblock rows at the bottom which are skipped", OFFSET(skip_bottom), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|D},
 {"profile", NULL, OFFSET(profile), FF_OPT_TYPE_INT, FF_PROFILE_UNKNOWN, INT_MIN, INT_MAX, V|A|E, "profile"},
 {"unknown", NULL, 0, FF_OPT_TYPE_CONST, FF_PROFILE_UNKNOWN, INT_MIN, INT_MAX, V|A|E, "profile"},
 {"level", NULL, OFFSET(level), FF_OPT_TYPE_INT, FF_LEVEL_UNKNOWN, INT_MIN, INT_MAX, V|A|E, "level"},
@@ -687,42 +687,42 @@ static const AVOption options[]={
 {"bidir_refine", "refine the two motion vectors used in bidirectional macroblocks", OFFSET(bidir_refine), FF_OPT_TYPE_INT, DEFAULT, 0, 4, V|E},
 {"brd_scale", "downscales frames for dynamic B-frame decision", OFFSET(brd_scale), FF_OPT_TYPE_INT, DEFAULT, 0, 10, V|E},
 {"crf", "enables constant quality mode, and selects the quality (x264)", OFFSET(crf), FF_OPT_TYPE_FLOAT, DEFAULT, 0, 51, V|E},
-{"cqp", NULL, OFFSET(cqp), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, V|E},
+{"cqp", "constant quantization parameter rate control method", OFFSET(cqp), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, V|E},
 {"keyint_min", "minimum interval between IDR-frames (x264)", OFFSET(keyint_min), FF_OPT_TYPE_INT, 25, INT_MIN, INT_MAX, V|E},
 {"refs", "reference frames to consider for motion compensation (Snow)", OFFSET(refs), FF_OPT_TYPE_INT, 1, INT_MIN, INT_MAX, V|E},
-{"chromaoffset", NULL, OFFSET(chromaoffset), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
-{"bframebias", NULL, OFFSET(bframebias), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
+{"chromaoffset", "chroma qp offset from luma", OFFSET(chromaoffset), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
+{"bframebias", "influences how often B-frames are used", OFFSET(bframebias), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
 {"trellis", "rate-distortion optimal quantization", OFFSET(trellis), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|A|E},
-{"directpred", NULL, OFFSET(directpred), FF_OPT_TYPE_INT, 2, INT_MIN, INT_MAX, V|E},
+{"directpred", "direct mv prediction mode - 0 (none), 1 (spatial), 2 (temporal)", OFFSET(directpred), FF_OPT_TYPE_INT, 2, INT_MIN, INT_MAX, V|E},
 {"bpyramid", "allows B-frames to be used as references for predicting", 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_BPYRAMID, INT_MIN, INT_MAX, V|E, "flags2"},
-{"wpred", NULL, 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_WPRED, INT_MIN, INT_MAX, V|E, "flags2"},
+{"wpred", "weighted biprediction for b-frames (H.264)", 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_WPRED, INT_MIN, INT_MAX, V|E, "flags2"},
 {"mixed_refs", NULL, 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_MIXED_REFS, INT_MIN, INT_MAX, V|E, "flags2"},
-{"8x8dct", NULL, 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_8X8DCT, INT_MIN, INT_MAX, V|E, "flags2"},
-{"fastpskip", NULL, 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_FASTPSKIP, INT_MIN, INT_MAX, V|E, "flags2"},
-{"aud", NULL, 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_AUD, INT_MIN, INT_MAX, V|E, "flags2"},
-{"brdo", NULL, 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_BRDO, INT_MIN, INT_MAX, V|E, "flags2"},
-{"complexityblur", NULL, OFFSET(complexityblur), FF_OPT_TYPE_FLOAT, 20.0, FLT_MIN, FLT_MAX, V|E},
-{"deblockalpha", NULL, OFFSET(deblockalpha), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
-{"deblockbeta", NULL, OFFSET(deblockbeta), FF_OPT_TYPE_INT, DEFAULT, INT_MIN, INT_MAX, V|E},
-{"partitions", NULL, OFFSET(partitions), FF_OPT_TYPE_FLAGS, DEFAULT, INT_MIN, INT_MAX, V|E, "partitions"},
+{"8x8dct", "high profile 8x8 transform (H.264)", 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_8X8DCT, INT_MIN, INT_MAX, V|E, "flags2"},
+{"fastpskip", "fast pskip (H.264)", 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_FASTPSKIP, INT_MIN, INT_MAX, V|E, "flags2"},
+{"aud", "access unit delimiters (H.264)", 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_AUD, INT_MIN, INT_MAX, V|E, "flags2"},
+{"brdo", "b-frame rate-distortion optimization", 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_BRDO, INT_MIN, INT_MAX, V|E, "flags2"},
+{"complexityblur", "reduce fluctuations in qp (before curve compression)", OFFSET(complexityblur), FF_OPT_TYPE_FLOAT, 20.0, FLT_MIN, FLT_MAX, V|E},
+{"deblockalpha", "in-loop deblocking filter alphac0 parameter", OFFSET(deblockalpha), FF_OPT_TYPE_INT, DEFAULT, -6, 6, V|E},
+{"deblockbeta", "in-loop deblocking filter beta parameter", OFFSET(deblockbeta), FF_OPT_TYPE_INT, DEFAULT, -6, 6, V|E},
+{"partitions", "macroblock subpartition sizes to consider", OFFSET(partitions), FF_OPT_TYPE_FLAGS, DEFAULT, INT_MIN, INT_MAX, V|E, "partitions"},
 {"parti4x4", NULL, 0, FF_OPT_TYPE_CONST, X264_PART_I4X4, INT_MIN, INT_MAX, V|E, "partitions"},
 {"parti8x8", NULL, 0, FF_OPT_TYPE_CONST, X264_PART_I8X8, INT_MIN, INT_MAX, V|E, "partitions"},
 {"partp4x4", NULL, 0, FF_OPT_TYPE_CONST, X264_PART_P4X4, INT_MIN, INT_MAX, V|E, "partitions"},
 {"partp8x8", NULL, 0, FF_OPT_TYPE_CONST, X264_PART_P8X8, INT_MIN, INT_MAX, V|E, "partitions"},
 {"partb8x8", NULL, 0, FF_OPT_TYPE_CONST, X264_PART_B8X8, INT_MIN, INT_MAX, V|E, "partitions"},
-{"sc_factor", NULL, OFFSET(scenechange_factor), FF_OPT_TYPE_INT, 6, 0, INT_MAX, V|E},
+{"sc_factor", "multiplied by qscale for each frame and added to scene_change_score", OFFSET(scenechange_factor), FF_OPT_TYPE_INT, 6, 0, INT_MAX, V|E},
 {"mv0_threshold", NULL, OFFSET(mv0_threshold), FF_OPT_TYPE_INT, 256, 0, INT_MAX, V|E},
 {"ivlc", "intra vlc table", 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_INTRA_VLC, INT_MIN, INT_MAX, V|E, "flags2"},
-{"b_sensitivity", NULL, OFFSET(b_sensitivity), FF_OPT_TYPE_INT, 40, 1, INT_MAX, V|E},
+{"b_sensitivity", "adjusts sensitivity of b_frame_strategy 1", OFFSET(b_sensitivity), FF_OPT_TYPE_INT, 40, 1, INT_MAX, V|E},
 {"compression_level", NULL, OFFSET(compression_level), FF_OPT_TYPE_INT, FF_COMPRESSION_DEFAULT, INT_MIN, INT_MAX, V|A|E},
-{"use_lpc", NULL, OFFSET(use_lpc), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
-{"lpc_coeff_precision", NULL, OFFSET(lpc_coeff_precision), FF_OPT_TYPE_INT, DEFAULT, 0, INT_MAX, A|E},
+{"use_lpc", "sets whether to use LPC mode (FLAC)", OFFSET(use_lpc), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
+{"lpc_coeff_precision", "LPC coefficient precision (FLAC)", OFFSET(lpc_coeff_precision), FF_OPT_TYPE_INT, DEFAULT, 0, INT_MAX, A|E},
 {"min_prediction_order", NULL, OFFSET(min_prediction_order), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
 {"max_prediction_order", NULL, OFFSET(max_prediction_order), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
-{"prediction_order_method", NULL, OFFSET(prediction_order_method), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
+{"prediction_order_method", "search method for selecting prediction order", OFFSET(prediction_order_method), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
 {"min_partition_order", NULL, OFFSET(min_partition_order), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
 {"max_partition_order", NULL, OFFSET(max_partition_order), FF_OPT_TYPE_INT, -1, INT_MIN, INT_MAX, A|E},
-{"timecode_frame_start", NULL, OFFSET(timecode_frame_start), FF_OPT_TYPE_INT, 0, 0, INT_MAX, V|E},
+{"timecode_frame_start", "GOP timecode frame start number, in non drop frame format", OFFSET(timecode_frame_start), FF_OPT_TYPE_INT, 0, 0, INT_MAX, V|E},
 {"drop_frame_timecode", NULL, 0, FF_OPT_TYPE_CONST, CODEC_FLAG2_DROP_FRAME_TIMECODE, INT_MIN, INT_MAX, V|E, "flags2"},
 {NULL},
 };