On macOS, a zero rc_max_rate cause an error from VTSessionSetProperty(kVTCompressionPropertyKey_DataRateLimits).
on iOS (depending on device/version), a zero rc_max_rate cause invalid arguments from the vtenc_output_callback after few frames and then a crash within the VideoToolbox library. --- libavcodec/videotoolboxenc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/libavcodec/videotoolboxenc.c b/libavcodec/videotoolboxenc.c index ac847358ab..aa9aae7e05 100644 --- a/libavcodec/videotoolboxenc.c +++ b/libavcodec/videotoolboxenc.c @@ -1019,6 +1019,7 @@ static int vtenc_create_encoder(AVCodecContext *avctx, if (vtctx->codec_id == AV_CODEC_ID_H264) { // kVTCompressionPropertyKey_DataRateLimits is not available for HEVC + if (max_rate > 0) { bytes_per_second_value = max_rate >> 3; bytes_per_second = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt64Type, @@ -1058,6 +1059,7 @@ static int vtenc_create_encoder(AVCodecContext *avctx, av_log(avctx, AV_LOG_ERROR, "Error setting max bitrate property: %d\n", status); return AVERROR_EXTERNAL; } + } if (profile_level) { status = VTSessionSetProperty(vtctx->session, -- 2.18.0 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel