From 28f20d2ff487aa589643d8f70eaf614b78839685 Mon Sep 17 00:00:00 2001 From: Giorgio Vazzana Date: Fri, 8 May 2015 17:25:15 +0200 Subject: lavd/v4l2: produce a 0 byte packet when a dequeued buffer is flagged with V4L2_BUF_FLAG_ERROR Fixes ticket #4030. Signed-off-by: Michael Niedermayer --- libavdevice/v4l2.c | 37 ++++++++++++++++++++++--------------- 1 file changed, 22 insertions(+), 15 deletions(-) (limited to 'libavdevice/v4l2.c') diff --git a/libavdevice/v4l2.c b/libavdevice/v4l2.c index ba7cd41dca..76f7c4ed1e 100644 --- a/libavdevice/v4l2.c +++ b/libavdevice/v4l2.c @@ -499,13 +499,14 @@ static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt) }; int res; + pkt->size = 0; + /* FIXME: Some special treatment might be needed in case of loss of signal... */ while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR)); if (res < 0) { - if (errno == EAGAIN) { - pkt->size = 0; + if (errno == EAGAIN) return AVERROR(EAGAIN); - } + res = AVERROR(errno); av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", av_err2str(res)); @@ -520,18 +521,24 @@ static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt) // always keep at least one buffer queued av_assert0(avpriv_atomic_int_get(&s->buffers_queued) >= 1); - /* CPIA is a compressed format and we don't know the exact number of bytes - * used by a frame, so set it here as the driver announces it. - */ - if (ctx->video_codec_id == AV_CODEC_ID_CPIA) - s->frame_size = buf.bytesused; + if (buf.flags & V4L2_BUF_FLAG_ERROR) { + av_log(ctx, AV_LOG_WARNING, + "Dequeued v4l2 buffer contains corrupted data (%d bytes).\n", + buf.bytesused); + buf.bytesused = 0; + } else { + /* CPIA is a compressed format and we don't know the exact number of bytes + * used by a frame, so set it here as the driver announces it. */ + if (ctx->video_codec_id == AV_CODEC_ID_CPIA) + s->frame_size = buf.bytesused; - if (s->frame_size > 0 && buf.bytesused != s->frame_size) { - av_log(ctx, AV_LOG_ERROR, - "The v4l2 frame is %d bytes, but %d bytes are expected. Flags: 0x%08X\n", - buf.bytesused, s->frame_size, buf.flags); - enqueue_buffer(s, &buf); - return AVERROR_INVALIDDATA; + if (s->frame_size > 0 && buf.bytesused != s->frame_size) { + av_log(ctx, AV_LOG_ERROR, + "Dequeued v4l2 buffer contains %d bytes, but %d were expected. Flags: 0x%08X.\n", + buf.bytesused, s->frame_size, buf.flags); + enqueue_buffer(s, &buf); + return AVERROR_INVALIDDATA; + } } /* Image is at s->buff_start[buf.index] */ @@ -586,7 +593,7 @@ FF_ENABLE_DEPRECATION_WARNINGS pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec; convert_timestamp(ctx, &pkt->pts); - return s->buf_len[buf.index]; + return pkt->size; } static int mmap_start(AVFormatContext *ctx) -- cgit v1.2.3