Simplify VMD demuxer (but it still does not work right)
authorKostya Shishkov <kostya.shishkov@gmail.com>
Mon, 13 Nov 2006 05:18:19 +0000 (05:18 +0000)
committerKostya Shishkov <kostya.shishkov@gmail.com>
Mon, 13 Nov 2006 05:18:19 +0000 (05:18 +0000)
Originally committed as revision 7001 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/sierravmd.c

index 9d861d0..bdb1807 100644 (file)
@@ -45,11 +45,6 @@ typedef struct VmdDemuxContext {
     int video_stream_index;
     int audio_stream_index;
 
-    unsigned int audio_type;
-    unsigned int audio_samplerate;
-    unsigned int audio_bits;
-    unsigned int audio_channels;
-
     unsigned int frame_count;
     unsigned int frames_per_block;
     vmd_frame_t *frame_table;
@@ -57,8 +52,6 @@ typedef struct VmdDemuxContext {
 
     int sample_rate;
     int64_t audio_sample_counter;
-    int audio_frame_divisor;
-    int audio_block_align;
     int skiphdr;
 
     unsigned char vmd_header[VMD_HEADER_SIZE];
@@ -78,79 +71,42 @@ static int vmd_probe(AVProbeData *p)
     return AVPROBE_SCORE_MAX / 2;
 }
 
-/* This is a support function to determine the duration, in sample
- * frames, of a particular audio chunk, taking into account silent
- * encodings. */
-static int vmd_calculate_audio_duration(unsigned char *audio_chunk,
-    int audio_chunk_size, int block_align)
-{
-    unsigned char *p = audio_chunk + 16;
-    unsigned char *p_end = audio_chunk + audio_chunk_size;
-    int total_samples = 0;
-    unsigned int sound_flags;
-
-    if (audio_chunk_size < 16)
-        return 0;
-    if (audio_chunk_size == block_align + 16)
-        return block_align;
-    if (audio_chunk_size == block_align + 17)
-        return block_align;
-
-    sound_flags = LE_32(p);
-    p += 4;
-    while (p < p_end) {
-        total_samples += block_align;
-        if ((sound_flags & 0x01) == 0)
-            p += block_align;
-        sound_flags >>= 1;
-    }
-    av_log(NULL,0,"Got %i samples for size %i map %08X\n", total_samples, audio_chunk_size, LE_32(audio_chunk));
-
-    return total_samples;
-}
-
 static int vmd_read_header(AVFormatContext *s,
                            AVFormatParameters *ap)
 {
     VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data;
     ByteIOContext *pb = &s->pb;
-    AVStream *st;
+    AVStream *st, *vst;
     unsigned int toc_offset;
     unsigned char *raw_frame_table;
     int raw_frame_table_size;
     offset_t current_offset;
     int i, j;
     unsigned int total_frames;
-    int64_t video_pts_inc = 0;
-    int64_t current_video_pts = 0;
+    int64_t pts_inc = 1;
+    int64_t current_video_pts = 0, current_audio_pts = 0;
     unsigned char chunk[BYTES_PER_FRAME_RECORD];
-    int lastframe = 0;
+    int num, den;
 
     /* fetch the main header, including the 2 header length bytes */
     url_fseek(pb, 0, SEEK_SET);
     if (get_buffer(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
         return AVERROR_IO;
 
-    vmd->audio_sample_counter = 0;
-    vmd->audio_frame_divisor = 1;
-    vmd->audio_block_align = 1;
-
     /* start up the decoders */
-    st = av_new_stream(s, 0);
-    if (!st)
+    vst = av_new_stream(s, 0);
+    if (!vst)
         return AVERROR_NOMEM;
-    av_set_pts_info(st, 33, 1, 90000);
-    vmd->video_stream_index = st->index;
-    st->codec->codec_type = CODEC_TYPE_VIDEO;
-    st->codec->codec_id = CODEC_ID_VMDVIDEO;
-    st->codec->codec_tag = 0;  /* no fourcc */
-    st->codec->width = LE_16(&vmd->vmd_header[12]);
-    st->codec->height = LE_16(&vmd->vmd_header[14]);
-    st->codec->time_base.num = 1;
-    st->codec->time_base.den = 10;
-    st->codec->extradata_size = VMD_HEADER_SIZE;
-    st->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
-    memcpy(st->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
+    av_set_pts_info(vst, 33, 1, 10);
+    vmd->video_stream_index = vst->index;
+    vst->codec->codec_type = CODEC_TYPE_VIDEO;
+    vst->codec->codec_id = CODEC_ID_VMDVIDEO;
+    vst->codec->codec_tag = 0;  /* no fourcc */
+    vst->codec->width = LE_16(&vmd->vmd_header[12]);
+    vst->codec->height = LE_16(&vmd->vmd_header[14]);
+    vst->codec->extradata_size = VMD_HEADER_SIZE;
+    vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
+    memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
 
     /* if sample rate is 0, assume no audio */
     vmd->sample_rate = LE_16(&vmd->vmd_header[804]);
@@ -158,35 +114,29 @@ static int vmd_read_header(AVFormatContext *s,
         st = av_new_stream(s, 0);
         if (!st)
             return AVERROR_NOMEM;
-        av_set_pts_info(st, 33, 1, 90000);
         vmd->audio_stream_index = st->index;
         st->codec->codec_type = CODEC_TYPE_AUDIO;
         st->codec->codec_id = CODEC_ID_VMDAUDIO;
         st->codec->codec_tag = 0;  /* no fourcc */
-        st->codec->channels = vmd->audio_channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
+        st->codec->channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
         st->codec->sample_rate = vmd->sample_rate;
-        st->codec->block_align = vmd->audio_block_align =
-            LE_16(&vmd->vmd_header[806]);
+        st->codec->block_align = LE_16(&vmd->vmd_header[806]);
         if (st->codec->block_align & 0x8000) {
             st->codec->bits_per_sample = 16;
             st->codec->block_align = -(st->codec->block_align - 0x10000);
-            vmd->audio_block_align = -(vmd->audio_block_align - 0x10000);
         } else {
             st->codec->bits_per_sample = 8;
         }
         st->codec->bit_rate = st->codec->sample_rate *
             st->codec->bits_per_sample * st->codec->channels;
 
-        /* for calculating pts */
-        vmd->audio_frame_divisor = st->codec->channels;
-
-        video_pts_inc = 90000;
-        video_pts_inc *= st->codec->block_align;
-        video_pts_inc /= st->codec->sample_rate;
-        video_pts_inc /= st->codec->channels;
-    } else {
-        /* if no audio, assume 10 frames/second */
-        video_pts_inc = 90000 / 10;
+        /* calculate pts */
+        num = st->codec->block_align;
+        den = st->codec->sample_rate * st->codec->channels;
+        av_reduce(&den, &num, den, num, (1UL<<31)-1);
+        av_set_pts_info(vst, 33, num, den);
+        av_set_pts_info(st, 33, num, den);
+        pts_inc = num;
     }
 
     toc_offset = LE_32(&vmd->vmd_header[812]);
@@ -236,24 +186,23 @@ static int vmd_read_header(AVFormatContext *s,
                 vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
                 vmd->frame_table[total_frames].frame_size = size;
                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
+                vmd->frame_table[total_frames].pts = current_audio_pts;
                 total_frames++;
+                /* first audio chunk contains several audio buffers */
+                current_audio_pts += (current_audio_pts == 0) ? LE_16(&vmd->vmd_header[808]) * pts_inc : pts_inc;
                 break;
             case 2: /* Video Chunk */
                 vmd->frame_table[total_frames].frame_offset = current_offset;
-                vmd->frame_table[total_frames].frame_size = size;
                 vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
+                vmd->frame_table[total_frames].frame_size = size;
                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
                 vmd->frame_table[total_frames].pts = current_video_pts;
-                if (lastframe) {
-                    vmd->frame_table[lastframe].pts = current_video_pts - video_pts_inc;
-                }
-                lastframe = total_frames;
                 total_frames++;
                 break;
             }
             current_offset += size;
         }
-        current_video_pts += video_pts_inc;
+        current_video_pts += pts_inc;
     }
 
     av_free(raw_frame_table);
@@ -291,21 +240,11 @@ static int vmd_read_packet(AVFormatContext *s,
         ret = AVERROR_IO;
     }
     pkt->stream_index = frame->stream_index;
-    if (frame->frame_record[0] == 0x02)
-        pkt->pts = frame->pts;
-    else {
-        pkt->pts = vmd->audio_sample_counter;
-        pkt->pts *= 90000;
-        pkt->pts /= vmd->sample_rate;
-        pkt->pts /= vmd->audio_channels;
-        vmd->audio_sample_counter += vmd_calculate_audio_duration(
-            pkt->data, pkt->size, vmd->audio_block_align);
-
-    }
-    av_log(NULL, AV_LOG_INFO, " dispatching %s frame with %d bytes and pts %"PRId64" (%0.1f sec)\n",
+    pkt->pts = frame->pts;
+    av_log(NULL, AV_LOG_INFO, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
             (frame->frame_record[0] == 0x02) ? "video" : "audio",
             frame->frame_size + BYTES_PER_FRAME_RECORD,
-            pkt->pts, (float)(pkt->pts / 90000.0));
+            pkt->pts);
 
     vmd->current_frame++;