Improved MP4 parsing (finally)

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@5302 b3059339-0415-0410-9bf9-f77b7e298cf2

1 files changed, 114 insertions, 0 deletions

diff --git a/libmpdemux/parse_mp4.c b/libmpdemux/parse_mp4.c
new file mode 100644
index 0000000000..e17703e6d5
--- /dev/null
+++ b/libmpdemux/parse_mp4.c
@@ -0,0 +1,114 @@
+/* parse_mp4.c - MP4 file format parser code
+ * This file is part of MPlayer, see http://mplayerhq.hu/ for info.  
+ * (c)2002 by Felix Buenemann <atmosfear at users.sourceforge.net>
+ * File licensed under the GPL, see http://www.fsf.org/ for more info.
+ * Code inspired by libmp4 from http://mpeg4ip.sourceforge.net/.
+ */
+   
+#include <stdio.h>
+#include <inttypes.h>
+#include <malloc.h>
+#include "parse_mp4.h"
+#include "mp_msg.h"
+#include "stream.h"
+
+#define MP4_DL MSGL_V
+
+int mp4_read_descr_len(stream_t *s) {
+  uint8_t b;
+  uint8_t numBytes = 0;
+  uint32_t length = 0;
+
+  do {
+    b = stream_read_char(s);
+    numBytes++;
+    length = (length << 7) | (b & 0x7F);
+  } while ((b & 0x80) && numBytes < 4);
+
+  return length;
+}
+
+int mp4_parse_esds(unsigned char *data, int datalen, esds_t *esds) {
+  /* create memory stream from data */
+  stream_t *s = new_memory_stream(data, datalen);
+  uint8_t tag;
+  uint8_t len;
+
+  esds->version = stream_read_char(s);
+  esds->flags = stream_read_int24(s);
+  mp_msg(MSGT_DEMUX, MP4_DL,
+      "ESDS MPEG4 version: %d  flags: 0x%06X\n",
+      esds->version, esds->flags);
+
+  /* get and verify ES_DescrTag */
+  tag = stream_read_char(s);
+  if (tag == MP4ESDescrTag) {
+    /* read length */
+    if ((len = mp4_read_descr_len(s)) < 5 + 15) {
+      return 1;
+    }
+    esds->ESId = stream_read_word(s);
+    esds->streamPriority = stream_read_char(s);
+  } else {
+#if 1 /* 1 == guessed */
+    esds->ESId = stream_read_word(s);
+#else    
+    /* skip 2 bytes */
+    stream_skip(s, 2);
+#endif
+  }
+  mp_msg(MSGT_DEMUX, MP4_DL,
+      "ESDS MPEG4 ES Descriptor (%dBytes):\n"
+      " -> ESId: %d\n"
+      " -> streamPriority: %d\n",
+      len, esds->ESId, esds->streamPriority);
+
+  /* get and verify DecoderConfigDescrTab */
+  if (stream_read_char(s) != MP4DecConfigDescrTag) {
+    return 1;
+  }
+
+  /* read length */
+  if ((len = mp4_read_descr_len(s)) < 15) {
+    return 1;
+  }
+
+  esds->objectTypeId = stream_read_char(s);
+  esds->streamType = stream_read_char(s);
+  esds->bufferSizeDB = stream_read_int24(s);
+  esds->maxBitrate = stream_read_dword(s);
+  esds->avgBitrate = stream_read_dword(s);
+  mp_msg(MSGT_DEMUX, MP4_DL,
+      "ESDS MPEG4 Decoder Config Descriptor (%dBytes):\n"
+      " -> objectTypeId: %d\n"
+      " -> streamType: 0x%02X\n"
+      " -> bufferSizeDB: 0x%06X\n"
+      " -> maxBitrate: %.3fkbit/s\n"
+      " -> avgBitrate: %.3fkbit/s\n",
+      len, esds->objectTypeId, esds->streamType,
+      esds->bufferSizeDB, esds->maxBitrate/1000.0,
+      esds->avgBitrate/1000.0);
+
+  /* get and verify DecSpecificInfoTag */
+  if (stream_read_char(s) != MP4DecSpecificDescrTag) {
+    return 1;
+  }
+
+  /* read length */
+  esds->decoderConfigLen = len = mp4_read_descr_len(s); 
+
+  free(esds->decoderConfig);
+  esds->decoderConfig = malloc(esds->decoderConfigLen);
+  if (esds->decoderConfig) {
+    stream_read(s, esds->decoderConfig, esds->decoderConfigLen);
+  } else {
+    esds->decoderConfigLen = 0;
+  }
+  mp_msg(MSGT_DEMUX, MP4_DL,
+      "ESDS MPEG4 Decoder Specific Descriptor (%dBytes)\n", len);
+
+  /* will skip the remainder of the atom */
+  return 0;
+
+}
+