From d9f07a506d230321f826dcb50828e1d10e852b44 Mon Sep 17 00:00:00 2001 From: Ryoji Gyoda Date: Mon, 22 Nov 2021 02:06:20 +0900 Subject: [PATCH] avformat/fifo: avoid repeated scaling of timestamps on failure and recovery If fifo_thread_recover() succeeds immediately after fifo_thread_dispatch_message() fails, the dts of the packet is scaled twice, causing cur_dts to be abnormally large and "Application provided invalid, non monotonically increasing dts to muxer in stream" to occur repeatedly. Steps to reproduce: 1. ffmpeg -f lavfi -i testsrc -c:v libx264 -map 0:v -flags +global_header -f fifo -fifo_format flv -attempt_recovery 1 -recover_any_error 1 rtmp://example.com/livekey 2. set a breakpoint on fifo_thread_recover 3. force disconnect from the rtmp server 4. wait for break 5. reconnect to the rtmp server 6. resume execution of ffmpeg Signed-off-by: Ryoji Gyoda Signed-off-by: Marton Balint --- libavformat/fifo.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/libavformat/fifo.c b/libavformat/fifo.c index 51d7fa5b94..2ee6dde830 100644 --- a/libavformat/fifo.c +++ b/libavformat/fifo.c @@ -183,6 +183,7 @@ static int fifo_thread_write_packet(FifoThreadContext *ctx, AVPacket *pkt) AVFormatContext *avf2 = fifo->avf; AVRational src_tb, dst_tb; int ret, s_idx; + int64_t orig_pts, orig_dts, orig_duration; if (fifo->timeshift && pkt->dts != AV_NOPTS_VALUE) atomic_fetch_sub_explicit(&fifo->queue_duration, next_duration(avf, pkt, &ctx->last_received_dts), memory_order_relaxed); @@ -198,14 +199,23 @@ static int fifo_thread_write_packet(FifoThreadContext *ctx, AVPacket *pkt) } } + orig_pts = pkt->pts; + orig_dts = pkt->dts; + orig_duration = pkt->duration; s_idx = pkt->stream_index; src_tb = avf->streams[s_idx]->time_base; dst_tb = avf2->streams[s_idx]->time_base; av_packet_rescale_ts(pkt, src_tb, dst_tb); ret = av_write_frame(avf2, pkt); - if (ret >= 0) + if (ret >= 0) { av_packet_unref(pkt); + } else { + // avoid scaling twice + pkt->pts = orig_pts; + pkt->dts = orig_dts; + pkt->duration = orig_duration; + } return ret; }