[FFmpeg-cvslog] avformat/movenc: utilize existing AC-3 parsing workflow for AC-3

[Jan Ekström]

ffmpeg | branch: master | Jan Ekström <jan.ekstrom at 24i.com> | Fri May  6 17:25:15 2022 +0300| [3854c58d9e55ba297b47c1840c159cd39b373b6a] | committer: Jan Ekström

avformat/movenc: utilize existing AC-3 parsing workflow for AC-3

Signed-off-by: Jan Ekström <jan.ekstrom at 24i.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=3854c58d9e55ba297b47c1840c159cd39b373b6a
---

 libavformat/movenc.c | 46 ++++++++++++++++++----------------------------
 1 file changed, 18 insertions(+), 28 deletions(-)

diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index b9e3f1a63e..96a34b75b0 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -363,44 +363,34 @@ struct eac3_info {
 
 static int mov_write_ac3_tag(AVFormatContext *s, AVIOContext *pb, MOVTrack *track)
 {
-    GetBitContext gbc;
+    struct eac3_info *info = track->eac3_priv;
     PutBitContext pbc;
     uint8_t buf[3];
-    int fscod, bsid, bsmod, acmod, lfeon, frmsizecod;
 
-    if (track->vos_len < 7) {
+    if (!info || !info->ec3_done) {
         av_log(s, AV_LOG_ERROR,
                "Cannot write moov atom before AC3 packets."
                " Set the delay_moov flag to fix this.\n");
         return AVERROR(EINVAL);
     }
 
+    if (info->ac3_bit_rate_code < 0) {
+        av_log(s, AV_LOG_ERROR,
+               "No valid AC3 bit rate code for data rate of %d!\n",
+               info->data_rate);
+        return AVERROR(EINVAL);
+    }
+
     avio_wb32(pb, 11);
     ffio_wfourcc(pb, "dac3");
 
-    init_get_bits(&gbc, track->vos_data + 4, (track->vos_len - 4) * 8);
-    fscod      = get_bits(&gbc, 2);
-    frmsizecod = get_bits(&gbc, 6);
-    bsid       = get_bits(&gbc, 5);
-    bsmod      = get_bits(&gbc, 3);
-    acmod      = get_bits(&gbc, 3);
-    if (acmod == 2) {
-        skip_bits(&gbc, 2); // dsurmod
-    } else {
-        if ((acmod & 1) && acmod != 1)
-            skip_bits(&gbc, 2); // cmixlev
-        if (acmod & 4)
-            skip_bits(&gbc, 2); // surmixlev
-    }
-    lfeon = get_bits1(&gbc);
-
     init_put_bits(&pbc, buf, sizeof(buf));
-    put_bits(&pbc, 2, fscod);
-    put_bits(&pbc, 5, bsid);
-    put_bits(&pbc, 3, bsmod);
-    put_bits(&pbc, 3, acmod);
-    put_bits(&pbc, 1, lfeon);
-    put_bits(&pbc, 5, frmsizecod >> 1); // bit_rate_code
+    put_bits(&pbc, 2, info->substream[0].fscod);
+    put_bits(&pbc, 5, info->substream[0].bsid);
+    put_bits(&pbc, 3, info->substream[0].bsmod);
+    put_bits(&pbc, 3, info->substream[0].acmod);
+    put_bits(&pbc, 1, info->substream[0].lfeon);
+    put_bits(&pbc, 5, info->ac3_bit_rate_code); // bit_rate_code
     put_bits(&pbc, 5, 0); // reserved
 
     flush_put_bits(&pbc);
@@ -6029,8 +6019,7 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
     if ((par->codec_id == AV_CODEC_ID_DNXHD ||
          par->codec_id == AV_CODEC_ID_H264 ||
          par->codec_id == AV_CODEC_ID_HEVC ||
-         par->codec_id == AV_CODEC_ID_TRUEHD ||
-         par->codec_id == AV_CODEC_ID_AC3) && !trk->vos_len &&
+         par->codec_id == AV_CODEC_ID_TRUEHD) && !trk->vos_len &&
          !TAG_IS_AVCI(trk->tag)) {
         /* copy frame to create needed atoms */
         trk->vos_len  = size;
@@ -6107,7 +6096,8 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
             }
         }
 
-    } else if (par->codec_id == AV_CODEC_ID_EAC3) {
+    } else if (par->codec_id == AV_CODEC_ID_AC3 ||
+               par->codec_id == AV_CODEC_ID_EAC3) {
         size = handle_eac3(mov, pkt, trk);
         if (size < 0)
             return size;