From 4b8b1415ae7709351eeab4037d0ef2e20bf9f7bd Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Tue, 30 Jan 2024 21:04:43 +0100 Subject: [PATCH] avcodec/vp8: Enforce key-frame only for WebP VP8-in-WebP only uses key frame encoding (see [1]), yet this is currently not enforced. This commit does so in order to make output reproducible with frame-threading as the VP8 decoder's update_thread_context is not called at all when using decoding VP8-in-WebP (as this is unnecessary for key frame-only streams). [1]: https://developers.google.com/speed/webp/docs/riff_container Signed-off-by: Andreas Rheinhardt --- libavcodec/vp8.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/libavcodec/vp8.c b/libavcodec/vp8.c index 83c60adeb0..7972775a1c 100644 --- a/libavcodec/vp8.c +++ b/libavcodec/vp8.c @@ -2665,7 +2665,11 @@ int vp78_decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, if (ret < 0) goto err; - if (s->actually_webp) { + if (!is_vp7 && s->actually_webp) { + // VP8 in WebP is supposed to be intra-only. Enforce this here + // to ensure that output is reproducible with frame-threading. + if (!s->keyframe) + return AVERROR_INVALIDDATA; // avctx->pix_fmt already set in caller. } else if (!is_vp7 && s->pix_fmt == AV_PIX_FMT_NONE) { s->pix_fmt = get_pixel_format(s);