[FFmpeg-devel] [PATCH] avcodec/bsf/h264_mp4toannexb.c: change extradata to annexb if this is avcc.

[jiangjie]

if get AV_PKT_DATA_NEW_EXTRADATA in AVPacket, this bitstream filter will return an error.
ffmpeg -i rtmp://xxx/live/xxx -bsf:v "h264_mp4toannexb,h264_metadata=aud=remove" -c copy -f null -
---
 libavcodec/bsf/h264_mp4toannexb.c | 26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/libavcodec/bsf/h264_mp4toannexb.c b/libavcodec/bsf/h264_mp4toannexb.c
index dda064287e..4cd002d166 100644
--- a/libavcodec/bsf/h264_mp4toannexb.c
+++ b/libavcodec/bsf/h264_mp4toannexb.c
@@ -252,14 +252,21 @@ static int h264_mp4toannexb_filter_ps(H264BSFContext *s,
     return 0;
 }
 
+static int is_annexb(const uint8_t *extradata, int extra_size) {
+    if (!extra_size || (extra_size >= 3 && AV_RB24(extradata) == 1) ||
+        (extra_size >= 4 && AV_RB32(extradata) == 1)) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
 static int h264_mp4toannexb_init(AVBSFContext *ctx)
 {
     int extra_size = ctx->par_in->extradata_size;
 
     /* retrieve sps and pps NAL units from extradata */
-    if (!extra_size                                               ||
-        (extra_size >= 3 && AV_RB24(ctx->par_in->extradata) == 1) ||
-        (extra_size >= 4 && AV_RB32(ctx->par_in->extradata) == 1)) {
+    if (is_annexb(ctx->par_in->extradata, extra_size)) {
         av_log(ctx, AV_LOG_VERBOSE,
                "The input looks like it is Annex B already\n");
     } else if (extra_size >= 7) {
@@ -294,9 +301,16 @@ static int h264_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *opkt)
     extradata = av_packet_get_side_data(in, AV_PKT_DATA_NEW_EXTRADATA,
                                         &extradata_size);
     if (extradata) {
-        ret = h264_extradata_to_annexb(ctx, extradata, extradata_size);
-        if (ret < 0)
-            goto fail;
+        if (!is_annexb(extradata, extradata_size) && extradata_size >= 7) {
+            ret = h264_extradata_to_annexb(ctx, extradata, extradata_size);
+            if (ret < 0)
+                goto fail;
+            av_packet_side_data_remove(in->side_data, &in->side_data_elems,
+                                       AV_PKT_DATA_NEW_EXTRADATA);
+            av_packet_add_side_data(in, AV_PKT_DATA_NEW_EXTRADATA,
+                                    ctx->par_out->extradata,
+                                    ctx->par_out->extradata_size);
+        }
     }
 
     /* nothing to filter */
-- 
2.49.0