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authorAurelien Jacobs <aurel@gnuage.org>2007-05-10 22:26:44 +0000
committerAurelien Jacobs <aurel@gnuage.org>2007-05-10 22:26:44 +0000
commit26b4fe821c0a6610e0d5598552e0a0e6114d4046 (patch)
tree6a3b04021db62ff8dbfe43917e822adabae5ad6e /libavcodec/h264_parser.c
parenteca3810e31a15c62b24408f5b4ae53f2c043911a (diff)
split h264.c to move parser in its own file
Originally committed as revision 8985 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/h264_parser.c')
-rw-r--r--libavcodec/h264_parser.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c
new file mode 100644
index 0000000000..4adb6cbe22
--- /dev/null
+++ b/libavcodec/h264_parser.c
@@ -0,0 +1,149 @@
+/*
+ * H.26L/H.264/AVC/JVT/14496-10/... parser
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * 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.
+ *
+ * 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+/**
+ * @file h264_parser.c
+ * H.264 / AVC / MPEG4 part10 parser.
+ * @author Michael Niedermayer <michaelni@gmx.at>
+ */
+
+#include "parser.h"
+#include "h264_parser.h"
+
+#include <assert.h>
+
+
+int ff_h264_find_frame_end(H264Context *h, const uint8_t *buf, int buf_size)
+{
+ int i;
+ uint32_t state;
+ ParseContext *pc = &(h->s.parse_context);
+//printf("first %02X%02X%02X%02X\n", buf[0], buf[1],buf[2],buf[3]);
+// mb_addr= pc->mb_addr - 1;
+ state= pc->state;
+ if(state>13)
+ state= 7;
+
+ for(i=0; i<buf_size; i++){
+ if(state==7){
+ for(; i<buf_size; i++){
+ if(!buf[i]){
+ state=2;
+ break;
+ }
+ }
+ }else if(state<=2){
+ if(buf[i]==1) state^= 5; //2->7, 1->4, 0->5
+ else if(buf[i]) state = 7;
+ else state>>=1; //2->1, 1->0, 0->0
+ }else if(state<=5){
+ int v= buf[i] & 0x1F;
+ if(v==7 || v==8 || v==9){
+ if(pc->frame_start_found){
+ i++;
+found:
+ pc->state=7;
+ pc->frame_start_found= 0;
+ return i-(state&5);
+ }
+ }else if(v==1 || v==2 || v==5){
+ if(pc->frame_start_found){
+ state+=8;
+ continue;
+ }else
+ pc->frame_start_found = 1;
+ }
+ state= 7;
+ }else{
+ if(buf[i] & 0x80)
+ goto found;
+ state= 7;
+ }
+ }
+ pc->state= state;
+ return END_NOT_FOUND;
+}
+
+static int h264_parse(AVCodecParserContext *s,
+ AVCodecContext *avctx,
+ const uint8_t **poutbuf, int *poutbuf_size,
+ const uint8_t *buf, int buf_size)
+{
+ H264Context *h = s->priv_data;
+ ParseContext *pc = &h->s.parse_context;
+ int next;
+
+ if(s->flags & PARSER_FLAG_COMPLETE_FRAMES){
+ next= buf_size;
+ }else{
+ next= ff_h264_find_frame_end(h, buf, buf_size);
+
+ if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
+ *poutbuf = NULL;
+ *poutbuf_size = 0;
+ return buf_size;
+ }
+
+ if(next<0 && next != END_NOT_FOUND){
+ assert(pc->last_index + next >= 0 );
+ ff_h264_find_frame_end(h, &pc->buffer[pc->last_index + next], -next); //update state
+ }
+ }
+
+ *poutbuf = buf;
+ *poutbuf_size = buf_size;
+ return next;
+}
+
+static int h264_split(AVCodecContext *avctx,
+ const uint8_t *buf, int buf_size)
+{
+ int i;
+ uint32_t state = -1;
+ int has_sps= 0;
+
+ for(i=0; i<=buf_size; i++){
+ if((state&0xFFFFFF1F) == 0x107)
+ has_sps=1;
+/* if((state&0xFFFFFF1F) == 0x101 || (state&0xFFFFFF1F) == 0x102 || (state&0xFFFFFF1F) == 0x105){
+ }*/
+ if((state&0xFFFFFF00) == 0x100 && (state&0xFFFFFF1F) != 0x107 && (state&0xFFFFFF1F) != 0x108 && (state&0xFFFFFF1F) != 0x109){
+ if(has_sps){
+ while(i>4 && buf[i-5]==0) i--;
+ return i-4;
+ }
+ }
+ if (i<buf_size)
+ state= (state<<8) | buf[i];
+ }
+ return 0;
+}
+
+
+AVCodecParser h264_parser = {
+ { CODEC_ID_H264 },
+ sizeof(H264Context),
+ NULL,
+ h264_parse,
+ ff_parse_close,
+ h264_split,
+};