avconv: get output pixel format from lavfi.

[ffmpeg] / libavformat / mxfdec.c

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index e70bc21bd09e513bf2ec289e043d553e98193cdd..dd102408db10fdb86e2bcd070a8e9b0db93f9446 100644 (file)
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -207,6 +207,7 @@ typedef struct {
     int current_edit_unit;
     int nb_index_tables;
     MXFIndexTable *index_tables;
+    int edit_units_per_packet;      ///< how many edit units to read at a time (PCM, OPAtom)
 } MXFContext;
 
 enum MXFWrappingScheme {
@@ -1130,11 +1131,15 @@ static int mxf_compute_ptses_fake_index(MXFContext *mxf, MXFIndexTable *index_ta
     for (i = x = 0; i < index_table->nb_segments; i++) {
         MXFIndexTableSegment *s = index_table->segments[i];
         int index_delta = 1;
+        int n = s->nb_index_entries;
 
-        if (s->nb_index_entries == 2 * s->index_duration + 1)
+        if (s->nb_index_entries == 2 * s->index_duration + 1) {
             index_delta = 2;    /* Avid index */
+            /* ignore the last entry - it's the size of the essence container */
+            n--;
+        }
 
-        for (j = 0; j < s->nb_index_entries; j += index_delta, x++) {
+        for (j = 0; j < n; j += index_delta, x++) {
             int offset = s->temporal_offset_entries[j] / index_delta;
             int index  = x + offset;
 
@@ -1430,7 +1435,10 @@ static int mxf_parse_structural_metadata(MXFContext *mxf)
                 st->codec->codec_id = container_ul->id;
             st->codec->channels = descriptor->channels;
             st->codec->bits_per_coded_sample = descriptor->bits_per_sample;
-            st->codec->sample_rate = descriptor->sample_rate.num / descriptor->sample_rate.den;
+
+            if (descriptor->sample_rate.den > 0)
+                st->codec->sample_rate = descriptor->sample_rate.num / descriptor->sample_rate.den;
+
             /* TODO: implement CODEC_ID_RAWAUDIO */
             if (st->codec->codec_id == CODEC_ID_PCM_S16LE) {
                 if (descriptor->bits_per_sample > 16 && descriptor->bits_per_sample <= 24)
@@ -1683,6 +1691,42 @@ static inline void compute_partition_essence_offset(AVFormatContext *s,
     }
 }
 
+static int is_pcm(enum CodecID codec_id)
+{
+    /* we only care about "normal" PCM codecs until we get samples */
+    return codec_id >= CODEC_ID_PCM_S16LE && codec_id < CODEC_ID_PCM_S24DAUD;
+}
+
+/**
+ * Deal with the case where for some audio atoms EditUnitByteCount is
+ * very small (2, 4..). In those cases we should read more than one
+ * sample per call to mxf_read_packet().
+ */
+static void mxf_handle_small_eubc(AVFormatContext *s)
+{
+    MXFContext *mxf = s->priv_data;
+
+    /* assuming non-OPAtom == frame wrapped
+     * no sane writer would wrap 2 byte PCM packets with 20 byte headers.. */
+    if (mxf->op != OPAtom)
+        return;
+
+    /* expect PCM with exactly one index table segment and a small (< 32) EUBC */
+    if (s->nb_streams != 1                                     ||
+        s->streams[0]->codec->codec_type != AVMEDIA_TYPE_AUDIO ||
+        !is_pcm(s->streams[0]->codec->codec_id)                ||
+        mxf->nb_index_tables != 1                              ||
+        mxf->index_tables[0].nb_segments != 1                  ||
+        mxf->index_tables[0].segments[0]->edit_unit_byte_count >= 32)
+        return;
+
+    /* arbitrarily default to 48 kHz PAL audio frame size */
+    /* TODO: We could compute this from the ratio between the audio
+     *       and video edit rates for 48 kHz NTSC we could use the
+     *       1802-1802-1802-1802-1801 pattern. */
+    mxf->edit_units_per_packet = 1920;
+}
+
 static int mxf_read_header(AVFormatContext *s)
 {
     MXFContext *mxf = s->priv_data;
@@ -1691,6 +1735,7 @@ static int mxf_read_header(AVFormatContext *s)
     int ret;
 
     mxf->last_forward_tell = INT64_MAX;
+    mxf->edit_units_per_packet = 1;
 
     if (!mxf_read_sync(s->pb, mxf_header_partition_pack_key, 14)) {
         av_log(s, AV_LOG_ERROR, "could not find header partition pack key\n");
@@ -1796,6 +1841,8 @@ static int mxf_read_header(AVFormatContext *s)
         return AVERROR_INVALIDDATA;
     }
 
+    mxf_handle_small_eubc(s);
+
     return 0;
 }
 
@@ -1897,6 +1944,7 @@ static int mxf_read_packet(AVFormatContext *s, AVPacket *pkt)
     int64_t ret64, pos, next_pos;
     AVStream *st;
     MXFIndexTable *t;
+    int edit_units;
 
     if (mxf->op != OPAtom)
         return mxf_read_packet_old(s, pkt);
@@ -1909,12 +1957,14 @@ static int mxf_read_packet(AVFormatContext *s, AVPacket *pkt)
     if (mxf->current_edit_unit >= st->duration)
         return AVERROR_EOF;
 
+    edit_units = FFMIN(mxf->edit_units_per_packet, st->duration - mxf->current_edit_unit);
+
     if ((ret = mxf_edit_unit_absolute_offset(mxf, t, mxf->current_edit_unit, NULL, &pos, 1)) < 0)
         return ret;
 
     /* compute size by finding the next edit unit or the end of the essence container
      * not pretty, but it works */
-    if ((ret = mxf_edit_unit_absolute_offset(mxf, t, mxf->current_edit_unit + 1, NULL, &next_pos, 0)) < 0 &&
+    if ((ret = mxf_edit_unit_absolute_offset(mxf, t, mxf->current_edit_unit + edit_units, NULL, &next_pos, 0)) < 0 &&
         (next_pos = mxf_essence_container_end(mxf, t->body_sid)) <= 0) {
         av_log(s, AV_LOG_ERROR, "unable to compute the size of the last packet\n");
         return AVERROR_INVALIDDATA;
@@ -1938,7 +1988,7 @@ static int mxf_read_packet(AVFormatContext *s, AVPacket *pkt)
     }
 
     pkt->stream_index = 0;
-    mxf->current_edit_unit++;
+    mxf->current_edit_unit += edit_units;
 
     return 0;
 }