[FFmpeg-soc] [soc]: r243 - dirac/dirac_parser.c

[marco]

Author: marco
Date: Sun Jun 10 16:17:50 2007
New Revision: 243

Log:
Add Dirac parser


Added:
   dirac/dirac_parser.c

Added: dirac/dirac_parser.c
==============================================================================
--- (empty file)
+++ dirac/dirac_parser.c	Sun Jun 10 16:17:50 2007
@@ -0,0 +1,94 @@
+/*
+ * Dirac parser
+ *
+ * Copyright (c) 2007 Marco Gerards <marco at gnu.org>
+ *
+ * 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
+ */
+
+#include "parser.h"
+
+#define DEBUG 1
+
+/**
+ * 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 find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size){
+     uint32_t state;
+
+    /* Check if there is enough room for a Parse Info Header,
+       otherwise stop.  */
+    if (buf_size < 13)
+        return END_NOT_FOUND;
+
+    state = pc->state;
+
+    if (pc->frame_start_found == 0) {
+        /* next_parse_offset has the amount of bytes to the next frame.  */
+        state = AV_RB32(buf + 5);
+    }
+
+    if (state > buf_size) {
+        /* The frame is not yet complete, use the state to store how
+           many bytes have to be read.  */
+        state -= buf_size;
+    } else {
+        pc->frame_start_found = 0;
+        pc->state = 0;
+
+        return state;
+    }
+
+    pc->frame_start_found = 1;
+    pc->state = state;
+
+    return END_NOT_FOUND;
+}
+
+static int dirac_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= find_frame_end(pc, 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 dirac_parser = {
+    { CODEC_ID_DIRAC },
+    sizeof(ParseContext),
+    NULL,
+    dirac_parse,
+    ff_parse_close,
+};