Relax error handling when examining FFmpeg files (#2187).

[dcpomatic.git] / src / lib / ffmpeg_examiner.cc

diff --git a/src/lib/ffmpeg_examiner.cc b/src/lib/ffmpeg_examiner.cc
index 632508e0ed3670f0e9fa89272751d4d1a9a28dec..3c6d185f43f0991d3716ad31e12dfb7b5f9dfd20 100644 (file)
--- a/src/lib/ffmpeg_examiner.cc
+++ b/src/lib/ffmpeg_examiner.cc
@@ -33,8 +33,9 @@ extern "C" {
 #include <libavformat/avformat.h>
 #include <libavutil/pixfmt.h>
 #include <libavutil/pixdesc.h>
-#include <libavutil/eval.h>
+#include <libavutil/channel_layout.h>
 #include <libavutil/display.h>
+#include <libavutil/eval.h>
 }
 DCPOMATIC_ENABLE_WARNINGS
 #include <iostream>
@@ -69,7 +70,8 @@ FFmpegExaminer::FFmpegExaminer (shared_ptr<const FFmpegContent> c, shared_ptr<Jo
 
        for (uint32_t i = 0; i < _format_context->nb_streams; ++i) {
                auto s = _format_context->streams[i];
-               if (s->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
+               auto codec = _codec_context[i] ? _codec_context[i]->codec : nullptr;
+               if (s->codecpar->codec_type == AVMEDIA_TYPE_AUDIO && codec) {
 
                        /* This is a hack; sometimes it seems that _audio_codec_context->channel_layout isn't set up,
                           so bodge it here.  No idea why we should have to do this.
@@ -79,10 +81,7 @@ FFmpegExaminer::FFmpegExaminer (shared_ptr<const FFmpegContent> c, shared_ptr<Jo
                                s->codecpar->channel_layout = av_get_default_channel_layout (s->codecpar->channels);
                        }
 
-                       auto codec = _codec_context[i]->codec;
-
                        DCPOMATIC_ASSERT (_format_context->duration != AV_NOPTS_VALUE);
-                       DCPOMATIC_ASSERT (codec);
                        DCPOMATIC_ASSERT (codec->name);
 
                        _audio_streams.push_back (
@@ -230,7 +229,7 @@ FFmpegExaminer::video_packet (AVCodecContext* context, string& temporal_referenc
                throw DecodeError (N_("avcodec_send_packet"), N_("FFmpegExaminer::video_packet"), r);
        }
 
-       r = avcodec_receive_frame (context, _frame);
+       r = avcodec_receive_frame (context, _video_frame);
        if (r == AVERROR(EAGAIN)) {
                /* More input is required */
                return true;
@@ -240,16 +239,17 @@ FFmpegExaminer::video_packet (AVCodecContext* context, string& temporal_referenc
        }
 
        if (!_first_video) {
-               _first_video = frame_time (_format_context->streams[_video_stream.get()]);
+               _first_video = frame_time (_video_frame, _format_context->streams[_video_stream.get()]);
        }
        if (_need_video_length) {
                _video_length = frame_time (
+                       _video_frame,
                        _format_context->streams[_video_stream.get()]
                        ).get_value_or (ContentTime ()).frames_round (video_frame_rate().get ());
        }
        if (temporal_reference.size() < (PULLDOWN_CHECK_FRAMES * 2)) {
-               temporal_reference += (_frame->top_field_first ? "T" : "B");
-               temporal_reference += (_frame->repeat_pict ? "3" : "2");
+               temporal_reference += (_video_frame->top_field_first ? "T" : "B");
+               temporal_reference += (_video_frame->repeat_pict ? "3" : "2");
        }
 
        return true;
@@ -264,30 +264,29 @@ FFmpegExaminer::audio_packet (AVCodecContext* context, shared_ptr<FFmpegAudioStr
        }
 
        int r = avcodec_send_packet (context, packet);
-       if (r < 0 && !(r == AVERROR_EOF && !packet) && r != AVERROR(EAGAIN)) {
-               /* We could cope with AVERROR(EAGAIN) and re-send the packet but I think it should never happen.
-                * AVERROR_EOF can happen during flush if we've already sent a flush packet.
-                * EAGAIN means we need to do avcodec_receive_frame, so just carry on and do that.
-                */
-               throw DecodeError (N_("avcodec_send_packet"), N_("FFmpegExaminer::audio_packet"), r);
+       if (r < 0) {
+               LOG_WARNING("avcodec_send_packet returned %1 for an audio packet", r);
+               return;
        }
 
-       if (avcodec_receive_frame (context, _frame) < 0) {
+       auto frame = audio_frame (stream);
+
+       if (avcodec_receive_frame (context, frame) < 0) {
                return;
        }
 
-       stream->first_audio = frame_time (stream->stream(_format_context));
+       stream->first_audio = frame_time (frame, stream->stream(_format_context));
 }
 
 
 optional<ContentTime>
-FFmpegExaminer::frame_time (AVStream* s) const
+FFmpegExaminer::frame_time (AVFrame* frame, AVStream* stream) const
 {
        optional<ContentTime> t;
 
-       int64_t const bet = _frame->best_effort_timestamp;
+       int64_t const bet = frame->best_effort_timestamp;
        if (bet != AV_NOPTS_VALUE) {
-               t = ContentTime::from_seconds (bet * av_q2d (s->time_base));
+               t = ContentTime::from_seconds (bet * av_q2d(stream->time_base));
        }
 
        return t;
@@ -481,3 +480,12 @@ FFmpegExaminer::range () const
                return VideoRange::FULL;
        }
 }
+
+
+PixelQuanta
+FFmpegExaminer::pixel_quanta () const
+{
+       auto const desc = av_pix_fmt_desc_get(video_codec_context()->pix_fmt);
+       return { 1 << desc->log2_chroma_w, 1 << desc->log2_chroma_h };
+}
+