diff options
Diffstat (limited to 'libavcodec/h264_parser.c')
| -rw-r--r-- | libavcodec/h264_parser.c | 104 |
1 files changed, 76 insertions, 28 deletions
diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c index 0464476..2628195 100644 --- a/libavcodec/h264_parser.c +++ b/libavcodec/h264_parser.c @@ -2,20 +2,20 @@ * H.26L/H.264/AVC/JVT/14496-10/... parser * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at> * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * - * Libav is distributed in the hope that it will be useful, + * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public - * License along with Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -25,38 +25,56 @@ * @author Michael Niedermayer <michaelni@gmx.at> */ +#define UNCHECKED_BITSTREAM_READER 1 + #include "parser.h" #include "h264data.h" #include "golomb.h" -#include <assert.h> - static int ff_h264_find_frame_end(H264Context *h, const uint8_t *buf, int buf_size) { - int i; + int i, j; uint32_t state; ParseContext *pc = &(h->s.parse_context); + int next_avc= h->is_avc ? 0 : buf_size; + // mb_addr= pc->mb_addr - 1; state= pc->state; if(state>13) state= 7; + if(h->is_avc && !h->nal_length_size) + av_log(h->s.avctx, AV_LOG_ERROR, "AVC-parser: nal length size invalid\n"); + for(i=0; i<buf_size; i++){ + if(i >= next_avc) { + int nalsize = 0; + i = next_avc; + for(j = 0; j < h->nal_length_size; j++) + nalsize = (nalsize << 8) | buf[i++]; + if(nalsize <= 0 || nalsize > buf_size - i){ + av_log(h->s.avctx, AV_LOG_ERROR, "AVC-parser: nal size %d remaining %d\n", nalsize, buf_size - i); + return buf_size; + } + next_avc= i + nalsize; + state= 5; + } + if(state==7){ #if HAVE_FAST_UNALIGNED /* we check i<buf_size instead of i+3/7 because its simpler * and there should be FF_INPUT_BUFFER_PADDING_SIZE bytes at the end */ # if HAVE_FAST_64BIT - while(i<buf_size && !((~*(const uint64_t*)(buf+i) & (*(const uint64_t*)(buf+i) - 0x0101010101010101ULL)) & 0x8080808080808080ULL)) + while(i<next_avc && !((~*(const uint64_t*)(buf+i) & (*(const uint64_t*)(buf+i) - 0x0101010101010101ULL)) & 0x8080808080808080ULL)) i+=8; # else - while(i<buf_size && !((~*(const uint32_t*)(buf+i) & (*(const uint32_t*)(buf+i) - 0x01010101U)) & 0x80808080U)) + while(i<next_avc && !((~*(const uint32_t*)(buf+i) & (*(const uint32_t*)(buf+i) - 0x01010101U)) & 0x80808080U)) i+=4; # endif #endif - for(; i<buf_size; i++){ + for(; i<next_avc; i++){ if(!buf[i]){ state=2; break; @@ -74,26 +92,41 @@ static int ff_h264_find_frame_end(H264Context *h, const uint8_t *buf, int buf_si goto found; } }else if(v==1 || v==2 || v==5){ + state+=8; + continue; + } + state= 7; + }else{ + h->parse_history[h->parse_history_count++]= buf[i]; + if(h->parse_history_count>3){ + unsigned int mb, last_mb= h->parse_last_mb; + GetBitContext gb; + + init_get_bits(&gb, h->parse_history, 8*h->parse_history_count); + h->parse_history_count=0; + mb= get_ue_golomb_long(&gb); + last_mb= h->parse_last_mb; + h->parse_last_mb= mb; if(pc->frame_start_found){ - state+=8; - continue; + if(mb <= last_mb) + goto found; }else pc->frame_start_found = 1; + state= 7; } - state= 7; - }else{ - if(buf[i] & 0x80) - goto found; - state= 7; } } pc->state= state; + if(h->is_avc) + return next_avc; return END_NOT_FOUND; found: pc->state=7; pc->frame_start_found= 0; - return i-(state&5); + if(h->is_avc) + return next_avc; + return i-(state&5) - 3*(state>7); } /** @@ -114,6 +147,7 @@ static inline int parse_nal_units(AVCodecParserContext *s, unsigned int slice_type; int state = -1; const uint8_t *ptr; + int q264 = buf_size >=4 && !memcmp("Q264", buf, 4); /* set some sane default values */ s->pict_type = AV_PICTURE_TYPE_I; @@ -129,12 +163,25 @@ static inline int parse_nal_units(AVCodecParserContext *s, return 0; for(;;) { - int src_length, dst_length, consumed; + int src_length, dst_length, consumed, nalsize = 0; + if (h->is_avc) { + int i; + if (h->nal_length_size >= buf_end - buf) break; + nalsize = 0; + for (i = 0; i < h->nal_length_size; i++) + nalsize = (nalsize << 8) | *buf++; + if (nalsize <= 0 || nalsize > buf_end - buf) { + av_log(h->s.avctx, AV_LOG_ERROR, "AVC: nal size %d\n", nalsize); + break; + } + src_length = nalsize; + } else { buf = avpriv_mpv_find_start_code(buf, buf_end, &state); if(buf >= buf_end) break; --buf; src_length = buf_end - buf; + } switch (state & 0x1f) { case NAL_SLICE: case NAL_IDR_SLICE: @@ -162,7 +209,7 @@ static inline int parse_nal_units(AVCodecParserContext *s, s->key_frame = 1; /* fall through */ case NAL_SLICE: - get_ue_golomb(&h->s.gb); // skip first_mb_in_slice + get_ue_golomb_long(&h->s.gb); // skip first_mb_in_slice slice_type = get_ue_golomb_31(&h->s.gb); s->pict_type = golomb_to_pict_type[slice_type % 5]; if (h->sei_recovery_frame_cnt >= 0) { @@ -230,10 +277,12 @@ static inline int parse_nal_units(AVCodecParserContext *s, return 0; /* no need to evaluate the rest */ } - buf += consumed; + buf += h->is_avc ? nalsize : consumed; } + if (q264) + return 0; /* didn't find a picture! */ - av_log(h->s.avctx, AV_LOG_ERROR, "missing picture in access unit\n"); + av_log(h->s.avctx, AV_LOG_ERROR, "missing picture in access unit with size %d\n", buf_size); return -1; } @@ -250,14 +299,13 @@ static int h264_parse(AVCodecParserContext *s, h->got_first = 1; if (avctx->extradata_size) { h->s.avctx = avctx; - // must be done like in the decoder. - // otherwise opening the parser, creating extradata, - // and then closing and opening again + // must be done like in decoder, otherwise opening the parser, + // letting it create extradata and then closing and opening again // will cause has_b_frames to be always set. - // NB: estimate_timings_from_pts behaves exactly like this. + // Note that estimate_timings_from_pts does exactly this. if (!avctx->has_b_frames) h->s.low_delay = 1; - ff_h264_decode_extradata(h); + ff_h264_decode_extradata(h, avctx->extradata, avctx->extradata_size); } } @@ -273,7 +321,7 @@ static int h264_parse(AVCodecParserContext *s, } if(next<0 && next != END_NOT_FOUND){ - assert(pc->last_index + next >= 0 ); + av_assert1(pc->last_index + next >= 0 ); ff_h264_find_frame_end(h, &pc->buffer[pc->last_index + next], -next); //update state } } |
