[FFmpeg-cvslog] mov: Refactor audio specific parsing in mov_parse_stsd_audio

Luca Barbato git at videolan.org
Mon Aug 26 13:18:49 CEST 2013


ffmpeg | branch: master | Luca Barbato <lu_zero at gentoo.org> | Thu Aug 22 15:05:27 2013 +0200| [ef196beeb50e8e024ed5a560a1d39eff4a296ce4] | committer: Luca Barbato

mov: Refactor audio specific parsing in mov_parse_stsd_audio

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=ef196beeb50e8e024ed5a560a1d39eff4a296ce4
---

 libavformat/mov.c |  165 ++++++++++++++++++++++++++++-------------------------
 1 file changed, 87 insertions(+), 78 deletions(-)

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 0c3f988..4100f33 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -1206,6 +1206,92 @@ static void mov_parse_stsd_video(MOVContext *c, AVIOContext *pb,
     }
 }
 
+static void mov_parse_stsd_audio(MOVContext *c, AVIOContext *pb,
+                                 AVStream *st, MOVStreamContext *sc)
+{
+    int bits_per_sample, flags;
+    uint16_t version = avio_rb16(pb);
+
+    avio_rb16(pb); /* revision level */
+    avio_rb32(pb); /* vendor */
+
+    st->codec->channels              = avio_rb16(pb); /* channel count */
+    st->codec->bits_per_coded_sample = avio_rb16(pb); /* sample size */
+    av_dlog(c->fc, "audio channels %d\n", st->codec->channels);
+
+    sc->audio_cid = avio_rb16(pb);
+    avio_rb16(pb); /* packet size = 0 */
+
+    st->codec->sample_rate = ((avio_rb32(pb) >> 16));
+
+    // Read QT version 1 fields. In version 0 these do not exist.
+    av_dlog(c->fc, "version =%d, isom =%d\n", version, c->isom);
+    if (!c->isom) {
+        if (version == 1) {
+            sc->samples_per_frame = avio_rb32(pb);
+            avio_rb32(pb); /* bytes per packet */
+            sc->bytes_per_frame = avio_rb32(pb);
+            avio_rb32(pb); /* bytes per sample */
+        } else if (version == 2) {
+            avio_rb32(pb); /* sizeof struct only */
+            st->codec->sample_rate = av_int2double(avio_rb64(pb));
+            st->codec->channels    = avio_rb32(pb);
+            avio_rb32(pb); /* always 0x7F000000 */
+            st->codec->bits_per_coded_sample = avio_rb32(pb);
+
+            flags = avio_rb32(pb); /* lpcm format specific flag */
+            sc->bytes_per_frame   = avio_rb32(pb);
+            sc->samples_per_frame = avio_rb32(pb);
+            if (st->codec->codec_tag == MKTAG('l','p','c','m'))
+                st->codec->codec_id =
+                    ff_mov_get_lpcm_codec_id(st->codec->bits_per_coded_sample,
+                                             flags);
+        }
+    }
+
+    switch (st->codec->codec_id) {
+    case AV_CODEC_ID_PCM_S8:
+    case AV_CODEC_ID_PCM_U8:
+        if (st->codec->bits_per_coded_sample == 16)
+            st->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
+        break;
+    case AV_CODEC_ID_PCM_S16LE:
+    case AV_CODEC_ID_PCM_S16BE:
+        if (st->codec->bits_per_coded_sample == 8)
+            st->codec->codec_id = AV_CODEC_ID_PCM_S8;
+        else if (st->codec->bits_per_coded_sample == 24)
+            st->codec->codec_id =
+                st->codec->codec_id == AV_CODEC_ID_PCM_S16BE ?
+                AV_CODEC_ID_PCM_S24BE : AV_CODEC_ID_PCM_S24LE;
+        break;
+    /* set values for old format before stsd version 1 appeared */
+    case AV_CODEC_ID_MACE3:
+        sc->samples_per_frame = 6;
+        sc->bytes_per_frame   = 2 * st->codec->channels;
+        break;
+    case AV_CODEC_ID_MACE6:
+        sc->samples_per_frame = 6;
+        sc->bytes_per_frame   = 1 * st->codec->channels;
+        break;
+    case AV_CODEC_ID_ADPCM_IMA_QT:
+        sc->samples_per_frame = 64;
+        sc->bytes_per_frame   = 34 * st->codec->channels;
+        break;
+    case AV_CODEC_ID_GSM:
+        sc->samples_per_frame = 160;
+        sc->bytes_per_frame   = 33;
+        break;
+    default:
+        break;
+    }
+
+    bits_per_sample = av_get_bits_per_sample(st->codec->codec_id);
+    if (bits_per_sample) {
+        st->codec->bits_per_coded_sample = bits_per_sample;
+        sc->sample_size = (bits_per_sample >> 3) * st->codec->channels;
+    }
+}
+
 int ff_mov_read_stsd_entries(MOVContext *c, AVIOContext *pb, int entries)
 {
     AVStream *st;
@@ -1266,85 +1352,8 @@ int ff_mov_read_stsd_entries(MOVContext *c, AVIOContext *pb, int entries)
             st->codec->codec_id = id;
             mov_parse_stsd_video(c, pb, st, sc);
         } else if (st->codec->codec_type==AVMEDIA_TYPE_AUDIO) {
-            int bits_per_sample, flags;
-            uint16_t version = avio_rb16(pb);
-
             st->codec->codec_id = id;
-            avio_rb16(pb); /* revision level */
-            avio_rb32(pb); /* vendor */
-
-            st->codec->channels = avio_rb16(pb);             /* channel count */
-            av_dlog(c->fc, "audio channels %d\n", st->codec->channels);
-            st->codec->bits_per_coded_sample = avio_rb16(pb);      /* sample size */
-
-            sc->audio_cid = avio_rb16(pb);
-            avio_rb16(pb); /* packet size = 0 */
-
-            st->codec->sample_rate = ((avio_rb32(pb) >> 16));
-
-            //Read QT version 1 fields. In version 0 these do not exist.
-            av_dlog(c->fc, "version =%d, isom =%d\n",version,c->isom);
-            if (!c->isom) {
-                if (version==1) {
-                    sc->samples_per_frame = avio_rb32(pb);
-                    avio_rb32(pb); /* bytes per packet */
-                    sc->bytes_per_frame = avio_rb32(pb);
-                    avio_rb32(pb); /* bytes per sample */
-                } else if (version==2) {
-                    avio_rb32(pb); /* sizeof struct only */
-                    st->codec->sample_rate = av_int2double(avio_rb64(pb)); /* float 64 */
-                    st->codec->channels = avio_rb32(pb);
-                    avio_rb32(pb); /* always 0x7F000000 */
-                    st->codec->bits_per_coded_sample = avio_rb32(pb); /* bits per channel if sound is uncompressed */
-                    flags = avio_rb32(pb); /* lpcm format specific flag */
-                    sc->bytes_per_frame = avio_rb32(pb); /* bytes per audio packet if constant */
-                    sc->samples_per_frame = avio_rb32(pb); /* lpcm frames per audio packet if constant */
-                    if (format == MKTAG('l','p','c','m'))
-                        st->codec->codec_id = ff_mov_get_lpcm_codec_id(st->codec->bits_per_coded_sample, flags);
-                }
-            }
-
-            switch (st->codec->codec_id) {
-            case AV_CODEC_ID_PCM_S8:
-            case AV_CODEC_ID_PCM_U8:
-                if (st->codec->bits_per_coded_sample == 16)
-                    st->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
-                break;
-            case AV_CODEC_ID_PCM_S16LE:
-            case AV_CODEC_ID_PCM_S16BE:
-                if (st->codec->bits_per_coded_sample == 8)
-                    st->codec->codec_id = AV_CODEC_ID_PCM_S8;
-                else if (st->codec->bits_per_coded_sample == 24)
-                    st->codec->codec_id =
-                        st->codec->codec_id == AV_CODEC_ID_PCM_S16BE ?
-                        AV_CODEC_ID_PCM_S24BE : AV_CODEC_ID_PCM_S24LE;
-                break;
-            /* set values for old format before stsd version 1 appeared */
-            case AV_CODEC_ID_MACE3:
-                sc->samples_per_frame = 6;
-                sc->bytes_per_frame = 2*st->codec->channels;
-                break;
-            case AV_CODEC_ID_MACE6:
-                sc->samples_per_frame = 6;
-                sc->bytes_per_frame = 1*st->codec->channels;
-                break;
-            case AV_CODEC_ID_ADPCM_IMA_QT:
-                sc->samples_per_frame = 64;
-                sc->bytes_per_frame = 34*st->codec->channels;
-                break;
-            case AV_CODEC_ID_GSM:
-                sc->samples_per_frame = 160;
-                sc->bytes_per_frame = 33;
-                break;
-            default:
-                break;
-            }
-
-            bits_per_sample = av_get_bits_per_sample(st->codec->codec_id);
-            if (bits_per_sample) {
-                st->codec->bits_per_coded_sample = bits_per_sample;
-                sc->sample_size = (bits_per_sample >> 3) * st->codec->channels;
-            }
+            mov_parse_stsd_audio(c, pb, st, sc);
         } else if (st->codec->codec_type==AVMEDIA_TYPE_SUBTITLE){
             // ttxt stsd contains display flags, justification, background
             // color, fonts, and default styles, so fake an atom to read it



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