[FFmpeg-devel] [PATCH 1/3] avcodec/libwebpenc_animencoder: Don't return pkt without data/side-data

[Andreas Rheinhardt]

They are essentially forbidden in our encoding API as they are
considered empty. So just set the data, but leave the size at zero.

(The old encoding API allowed such packets: It used buffer_pkt_valid
to record whether the packet is empty or not. This has been changed
in 827d6fe73d2f5472c1c2128eb14fab6a4db29032 which broke said encoder.
Said regression has been reported in #9179 which this commit partially
fixes.)

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
 libavcodec/libwebpenc_animencoder.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/libwebpenc_animencoder.c b/libavcodec/libwebpenc_animencoder.c
index 7f35a0b939..d871e85d43 100644
--- a/libavcodec/libwebpenc_animencoder.c
+++ b/libavcodec/libwebpenc_animencoder.c
@@ -34,6 +34,7 @@ typedef struct LibWebPAnimContext {
     WebPAnimEncoder *enc;     // the main AnimEncoder object
     int64_t prev_frame_pts;   // pts of the previously encoded frame.
     int done;                 // If true, we have assembled the bitstream already
+    uint8_t padding_buf[AV_INPUT_BUFFER_PADDING_SIZE];
 } LibWebPAnimContext;
 
 static av_cold int libwebp_anim_encode_init(AVCodecContext *avctx)
@@ -103,6 +104,8 @@ static int libwebp_anim_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
         }
 
         pkt->pts = pkt->dts = frame->pts;
+        // Packets without data and side-data are not supported by the API
+        pkt->data = s->padding_buf;
         s->prev_frame_pts = frame->pts;  // Save for next frame.
         ret = 0;
         *got_packet = 1;
-- 
2.27.0