[FFmpeg-cvslog] avformat/movenc: Simplify creating chapter track extradata

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Fri Mar  4 14:25:58 2022 +0100| [707ad03096b29de53f1a27c128891a81a7d6d7c2] | committer: Andreas Rheinhardt

avformat/movenc: Simplify creating chapter track extradata

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=707ad03096b29de53f1a27c128891a81a7d6d7c2
---

 libavformat/movenc.c | 79 +++++++++++++++++-----------------------------------
 1 file changed, 26 insertions(+), 53 deletions(-)

diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index 4c868919ae..2a6cc1bc6a 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -6238,12 +6238,32 @@ fail:
 // as samples, and a tref pointing from the other tracks to the chapter one.
 static int mov_create_chapter_track(AVFormatContext *s, int tracknum)
 {
-    AVIOContext *pb;
-
+    static const uint8_t stub_header[] = {
+        // TextSampleEntry
+        0x00, 0x00, 0x00, 0x01, // displayFlags
+        0x00, 0x00,             // horizontal + vertical justification
+        0x00, 0x00, 0x00, 0x00, // bgColourRed/Green/Blue/Alpha
+        // BoxRecord
+        0x00, 0x00, 0x00, 0x00, // defTextBoxTop/Left
+        0x00, 0x00, 0x00, 0x00, // defTextBoxBottom/Right
+        // StyleRecord
+        0x00, 0x00, 0x00, 0x00, // startChar + endChar
+        0x00, 0x01,             // fontID
+        0x00, 0x00,             // fontStyleFlags + fontSize
+        0x00, 0x00, 0x00, 0x00, // fgColourRed/Green/Blue/Alpha
+        // FontTableBox
+        0x00, 0x00, 0x00, 0x0D, // box size
+        'f', 't', 'a', 'b',     // box atom name
+        0x00, 0x01,             // entry count
+        // FontRecord
+        0x00, 0x01,             // font ID
+        0x00,                   // font name length
+    };
     MOVMuxContext *mov = s->priv_data;
     MOVTrack *track = &mov->tracks[tracknum];
     AVPacket *pkt = mov->pkt;
     int i, len;
+    int ret;
 
     track->mode = mov->mode;
     track->tag = MKTAG('t','e','x','t');
@@ -6252,57 +6272,10 @@ static int mov_create_chapter_track(AVFormatContext *s, int tracknum)
     if (!track->par)
         return AVERROR(ENOMEM);
     track->par->codec_type = AVMEDIA_TYPE_SUBTITLE;
-#if 0
-    // These properties are required to make QT recognize the chapter track
-    uint8_t chapter_properties[43] = { 0, 0, 0, 0, 0, 0, 0, 1, };
-    if (ff_alloc_extradata(track->par, sizeof(chapter_properties)))
-        return AVERROR(ENOMEM);
-    memcpy(track->par->extradata, chapter_properties, sizeof(chapter_properties));
-#else
-    if (avio_open_dyn_buf(&pb) >= 0) {
-        int size;
-        uint8_t *buf;
-
-        /* Stub header (usually for Quicktime chapter track) */
-        // TextSampleEntry
-        avio_wb32(pb, 0x01); // displayFlags
-        avio_w8(pb, 0x00);   // horizontal justification
-        avio_w8(pb, 0x00);   // vertical justification
-        avio_w8(pb, 0x00);   // bgColourRed
-        avio_w8(pb, 0x00);   // bgColourGreen
-        avio_w8(pb, 0x00);   // bgColourBlue
-        avio_w8(pb, 0x00);   // bgColourAlpha
-        // BoxRecord
-        avio_wb16(pb, 0x00); // defTextBoxTop
-        avio_wb16(pb, 0x00); // defTextBoxLeft
-        avio_wb16(pb, 0x00); // defTextBoxBottom
-        avio_wb16(pb, 0x00); // defTextBoxRight
-        // StyleRecord
-        avio_wb16(pb, 0x00); // startChar
-        avio_wb16(pb, 0x00); // endChar
-        avio_wb16(pb, 0x01); // fontID
-        avio_w8(pb, 0x00);   // fontStyleFlags
-        avio_w8(pb, 0x00);   // fontSize
-        avio_w8(pb, 0x00);   // fgColourRed
-        avio_w8(pb, 0x00);   // fgColourGreen
-        avio_w8(pb, 0x00);   // fgColourBlue
-        avio_w8(pb, 0x00);   // fgColourAlpha
-        // FontTableBox
-        avio_wb32(pb, 0x0D); // box size
-        ffio_wfourcc(pb, "ftab"); // box atom name
-        avio_wb16(pb, 0x01); // entry count
-        // FontRecord
-        avio_wb16(pb, 0x01); // font ID
-        avio_w8(pb, 0x00);   // font name length
-
-        if ((size = avio_close_dyn_buf(pb, &buf)) > 0) {
-            track->par->extradata = buf;
-            track->par->extradata_size = size;
-        } else {
-            av_freep(&buf);
-        }
-    }
-#endif
+    ret = ff_alloc_extradata(track->par, sizeof(stub_header));
+    if (ret < 0)
+        return ret;
+    memcpy(track->par->extradata, stub_header, sizeof(stub_header));
 
     pkt->stream_index = tracknum;
     pkt->flags = AV_PKT_FLAG_KEY;