1 files changed, 93 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/h261_parser.c b/ffmpeg/libavcodec/h261_parser.c
new file mode 100644
index 0000000..753687a
--- /dev/null
+++ b/ffmpeg/libavcodec/h261_parser.c
@@ -0,0 +1,93 @@
+/*
+ * H261 parser
+ * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
+ * Copyright (c) 2004 Maarten Daniels
+ *
+ * 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
+ * h261codec.
+ */
+
+#include "parser.h"
+
+
+static int h261_find_frame_end(ParseContext *pc, AVCodecContext* avctx, const uint8_t *buf, int buf_size){
+    int vop_found, i, j;
+    uint32_t state;
+
+    vop_found= pc->frame_start_found;
+    state= pc->state;
+
+    for(i=0; i<buf_size && !vop_found; i++){
+        state= (state<<8) | buf[i];
+        for(j=0; j<8; j++){
+            if(((state>>j)&0xFFFFF0) == 0x000100){
+                vop_found=1;
+                break;
+            }
+        }
+    }
+    if(vop_found){
+        for(; i<buf_size; i++){
+            state= (state<<8) | buf[i];
+            for(j=0; j<8; j++){
+                if(((state>>j)&0xFFFFF0) == 0x000100){
+                    pc->frame_start_found=0;
+                    pc->state= (state>>(3*8))+0xFF00;
+                    return i-2;
+                }
+            }
+        }
+    }
+
+    pc->frame_start_found= vop_found;
+    pc->state= state;
+    return END_NOT_FOUND;
+}
+
+static int h261_parse(AVCodecParserContext *s,
+                      AVCodecContext *avctx,
+                      const 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= h261_find_frame_end(pc,avctx, buf, buf_size);
+        if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
+            *poutbuf = NULL;
+            *poutbuf_size = 0;
+            return buf_size;
+        }
+    }
+    *poutbuf = buf;
+    *poutbuf_size = buf_size;
+    return next;
+}
+
+AVCodecParser ff_h261_parser = {
+    .codec_ids      = { AV_CODEC_ID_H261 },
+    .priv_data_size = sizeof(ParseContext),
+    .parser_parse   = h261_parse,
+    .parser_close   = ff_parse_close,
+};