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authorDiego Biurrun <diego@biurrun.de>2007-05-04 00:09:33 +0000
committerDiego Biurrun <diego@biurrun.de>2007-05-04 00:09:33 +0000
commit5982ae94eef6b0d0ef23f33cc8759c8d6e1ab736 (patch)
tree937730e6f97ed5df16ed87e991685193fc3c9b7e /libavcodec/vc1_parser.c
parent98c98e04ccae75ccaf0f3ebf18588bc0090dff8b (diff)
Move VC1 parser to its own file.
Originally committed as revision 8882 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/vc1_parser.c')
-rw-r--r--libavcodec/vc1_parser.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/libavcodec/vc1_parser.c b/libavcodec/vc1_parser.c
new file mode 100644
index 0000000000..1476f9c229
--- /dev/null
+++ b/libavcodec/vc1_parser.c
@@ -0,0 +1,118 @@
+/*
+ * VC-1 and WMV3 parser
+ * Copyright (c) 2006-2007 Konstantin Shishkov
+ * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer
+ *
+ * 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 vc1_parser.c
+ * VC-1 and WMV3 parser
+ */
+#include "dsputil.h"
+#include "parser.h"
+#include "vc1.h"
+
+/**
+ * finds the end of the current frame in the bitstream.
+ * @return the position of the first byte of the next frame, or -1
+ */
+static int vc1_find_frame_end(ParseContext *pc, const uint8_t *buf,
+ int buf_size) {
+ int pic_found, i;
+ uint32_t state;
+
+ pic_found= pc->frame_start_found;
+ state= pc->state;
+
+ i=0;
+ if(!pic_found){
+ for(i=0; i<buf_size; i++){
+ state= (state<<8) | buf[i];
+ if(state == VC1_CODE_FRAME || state == VC1_CODE_FIELD){
+ i++;
+ pic_found=1;
+ break;
+ }
+ }
+ }
+
+ if(pic_found){
+ /* EOF considered as end of frame */
+ if (buf_size == 0)
+ return 0;
+ for(; i<buf_size; i++){
+ state= (state<<8) | buf[i];
+ if(IS_MARKER(state) && state != VC1_CODE_FIELD && state != VC1_CODE_SLICE){
+ pc->frame_start_found=0;
+ pc->state=-1;
+ return i-3;
+ }
+ }
+ }
+ pc->frame_start_found= pic_found;
+ pc->state= state;
+ return END_NOT_FOUND;
+}
+
+static int vc1_parse(AVCodecParserContext *s,
+ AVCodecContext *avctx,
+ uint8_t **poutbuf, int *poutbuf_size,
+ const uint8_t *buf, int buf_size)
+{
+ ParseContext *pc = s->priv_data;
+ int next;
+
+ if(s->flags & PARSER_FLAG_COMPLETE_FRAMES){
+ next= buf_size;
+ }else{
+ next= vc1_find_frame_end(pc, buf, buf_size);
+
+ if (ff_combine_frame(pc, next, (uint8_t **)&buf, &buf_size) < 0) {
+ *poutbuf = NULL;
+ *poutbuf_size = 0;
+ return buf_size;
+ }
+ }
+ *poutbuf = (uint8_t *)buf;
+ *poutbuf_size = buf_size;
+ return next;
+}
+
+static int vc1_split(AVCodecContext *avctx,
+ const uint8_t *buf, int buf_size)
+{
+ int i;
+ uint32_t state= -1;
+
+ for(i=0; i<buf_size; i++){
+ state= (state<<8) | buf[i];
+ if(IS_MARKER(state) && state != VC1_CODE_SEQHDR && state != VC1_CODE_ENTRYPOINT)
+ return i-3;
+ }
+ return 0;
+}
+
+AVCodecParser vc1_parser = {
+ { CODEC_ID_VC1 },
+ sizeof(ParseContext1),
+ NULL,
+ vc1_parse,
+ ff_parse1_close,
+ vc1_split,
+};