Set video width/height and create audio stream in read_packet instead of

pre-parsing the file in read_header.
This avoids some code duplication and seeking, and also avoids an IO error
for small video-only files (as created during e.g. the FATE encoder test).

Originally committed as revision 17945 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/idroq.c

@@ -73,9 +73,6 @@ static int roq_read_header(AVFormatContext *s,
     ByteIOContext *pb = s->pb;
     AVStream *st;
     unsigned char preamble[RoQ_CHUNK_PREAMBLE_SIZE];
-    int i;
-    unsigned int chunk_size;
-    unsigned int chunk_type;
 
     /* get the main header */
     if (get_buffer(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) !=
@@ -87,58 +84,8 @@ static int roq_read_header(AVFormatContext *s,
     /* init private context parameters */
     roq->width = roq->height = roq->audio_channels = roq->video_pts =
     roq->audio_frame_count = 0;
+    roq->audio_stream_index = -1;
 
-    /* scan the first n chunks searching for A/V parameters */
-    for (i = 0; i < RoQ_CHUNKS_TO_SCAN; i++) {
-        if (get_buffer(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) !=
-            RoQ_CHUNK_PREAMBLE_SIZE)
-            return AVERROR(EIO);
-
-        chunk_type = AV_RL16(&preamble[0]);
-        chunk_size = AV_RL32(&preamble[2]);
-
-        switch (chunk_type) {
-
-        case RoQ_INFO:
-            /* fetch the width and height; reuse the preamble bytes */
-            if (get_buffer(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) !=
-                RoQ_CHUNK_PREAMBLE_SIZE)
-                return AVERROR(EIO);
-            roq->width = AV_RL16(&preamble[0]);
-            roq->height = AV_RL16(&preamble[2]);
-            break;
-
-        case RoQ_QUAD_CODEBOOK:
-        case RoQ_QUAD_VQ:
-            /* ignore during this scan */
-            url_fseek(pb, chunk_size, SEEK_CUR);
-            break;
-
-        case RoQ_SOUND_MONO:
-            roq->audio_channels = 1;
-            url_fseek(pb, chunk_size, SEEK_CUR);
-            break;
-
-        case RoQ_SOUND_STEREO:
-            roq->audio_channels = 2;
-            url_fseek(pb, chunk_size, SEEK_CUR);
-            break;
-
-        default:
-            av_log(s, AV_LOG_ERROR, " unknown RoQ chunk type (%04X)\n", AV_RL16(&preamble[0]));
-            return AVERROR_INVALIDDATA;
-            break;
-        }
-
-        /* if all necessary parameters have been gathered, exit early */
-        if ((roq->width && roq->height) && roq->audio_channels)
-            break;
-    }
-
-    /* seek back to the first chunk */
-    url_fseek(pb, RoQ_CHUNK_PREAMBLE_SIZE, SEEK_SET);
-
-    /* initialize the decoders */
     st = av_new_stream(s, 0);
     if (!st)
         return AVERROR(ENOMEM);
@@ -148,25 +95,6 @@ static int roq_read_header(AVFormatContext *s,
     st->codec->codec_type = CODEC_TYPE_VIDEO;
     st->codec->codec_id = CODEC_ID_ROQ;
     st->codec->codec_tag = 0;  /* no fourcc */
-    st->codec->width = roq->width;
-    st->codec->height = roq->height;
-
-    if (roq->audio_channels) {
-        st = av_new_stream(s, 0);
-        if (!st)
-            return AVERROR(ENOMEM);
-        av_set_pts_info(st, 33, 1, 90000);
-        roq->audio_stream_index = st->index;
-        st->codec->codec_type = CODEC_TYPE_AUDIO;
-        st->codec->codec_id = CODEC_ID_ROQ_DPCM;
-        st->codec->codec_tag = 0;  /* no tag */
-        st->codec->channels = roq->audio_channels;
-        st->codec->sample_rate = RoQ_AUDIO_SAMPLE_RATE;
-        st->codec->bits_per_coded_sample = 16;
-        st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
-            st->codec->bits_per_coded_sample;
-        st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
-    }
 
     return 0;
 }
@@ -202,6 +130,14 @@ static int roq_read_packet(AVFormatContext *s,
         switch (chunk_type) {
 
         case RoQ_INFO:
+            if (!roq->width || !roq->height) {
+                AVStream *st = s->streams[roq->video_stream_index];
+                if (get_buffer(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) != RoQ_CHUNK_PREAMBLE_SIZE)
+                    return AVERROR(EIO);
+                st->codec->width  = roq->width  = AV_RL16(preamble);
+                st->codec->height = roq->height = AV_RL16(preamble + 2);
+                break;
+            }
             /* don't care about this chunk anymore */
             url_fseek(pb, RoQ_CHUNK_PREAMBLE_SIZE, SEEK_CUR);
             break;
@@ -233,6 +169,22 @@ static int roq_read_packet(AVFormatContext *s,
 
         case RoQ_SOUND_MONO:
         case RoQ_SOUND_STEREO:
+            if (roq->audio_stream_index == -1) {
+                AVStream *st = av_new_stream(s, 1);
+                if (!st)
+                    return AVERROR(ENOMEM);
+                av_set_pts_info(st, 33, 1, 90000);
+                roq->audio_stream_index = st->index;
+                st->codec->codec_type = CODEC_TYPE_AUDIO;
+                st->codec->codec_id = CODEC_ID_ROQ_DPCM;
+                st->codec->codec_tag = 0;  /* no tag */
+                st->codec->channels = roq->audio_channels = chunk_type == RoQ_SOUND_STEREO ? 2 : 1;
+                st->codec->sample_rate = RoQ_AUDIO_SAMPLE_RATE;
+                st->codec->bits_per_coded_sample = 16;
+                st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
+                    st->codec->bits_per_coded_sample;
+                st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
+            }
         case RoQ_QUAD_VQ:
             /* load up the packet */
             if (av_new_packet(pkt, chunk_size + RoQ_CHUNK_PREAMBLE_SIZE))