Make Video Decoding more stable

gui/CMakeLists.txt

@@ -13,6 +13,7 @@ endif()
 find_package(FFMPEG REQUIRED COMPONENTS avcodec)
 
 add_executable(chiaki
+		include/exception.h
 		src/main.cpp
 		include/streamwindow.h
 		src/streamwindow.cpp

gui/include/exception.h

@@ -0,0 +1,35 @@
+/*
+ * This file is part of Chiaki.
+ *
+ * Chiaki is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Chiaki is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Chiaki.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef CHIAKI_EXCEPTION_H
+#define CHIAKI_EXCEPTION_H
+
+#include <exception>
+
+#include <QString>
+
+class Exception : public std::exception
+{
+	private:
+		QString msg;
+
+	public:
+		explicit Exception(const QString &msg) : msg(msg) {}
+		const char *what() const noexcept override { return msg.toLocal8Bit().constData(); }
+};
+
+#endif // CHIAKI_EXCEPTION_H

gui/include/streamsession.h

@@ -19,6 +19,7 @@
 #define CHIAKI_STREAMSESSION_H
 
 #include "videodecoder.h"
+#include "exception.h"
 
 #include <QObject>
 #include <QImage>
@@ -33,14 +34,10 @@ class QAudioOutput;
 class QIODevice;
 class QKeyEvent;
 
-class ChiakiException : public std::exception
+class ChiakiException: public Exception
 {
-	private:
-		QString msg;
-
 	public:
-		explicit ChiakiException(const QString &msg) : msg(msg) {}
-		const char *what() const noexcept override { return msg.toLocal8Bit().constData(); }
+		explicit ChiakiException(const QString &msg) : Exception(msg) {};
 };
 
 struct StreamSessionConnectInfo

gui/include/videodecoder.h

@@ -18,6 +18,8 @@
 #ifndef CHIAKI_VIDEODECODER_H
 #define CHIAKI_VIDEODECODER_H
 
+#include "exception.h"
+
 #include <QMutex>
 #include <QObject>
 
@@ -28,6 +30,12 @@ extern "C"
 
 #include <cstdint>
 
+class VideoDecoderException: public Exception
+{
+	public:
+		explicit VideoDecoderException(const QString &msg) : Exception(msg) {};
+};
+
 class VideoDecoder: public QObject
 {
 	Q_OBJECT

gui/src/videodecoder.cpp

@@ -23,20 +23,25 @@
 
 VideoDecoder::VideoDecoder()
 {
-	codec = avcodec_find_decoder(AV_CODEC_ID_H264); // TODO: handle !codec
-	codec_context = avcodec_alloc_context3(codec); // TODO: handle !codec_context
+	codec = avcodec_find_decoder(AV_CODEC_ID_H264);
+	if(!codec)
+		throw VideoDecoderException("H264 Codec not available");
 
-	if(codec->capabilities & AV_CODEC_CAP_TRUNCATED)
-		codec_context->flags |= AV_CODEC_FLAG_TRUNCATED;
+	codec_context = avcodec_alloc_context3(codec);
+	if(!codec_context)
+		throw VideoDecoderException("Failed to alloc codec context");
 
-	avcodec_open2(codec_context, codec, nullptr); // TODO: handle < 0
+	if(avcodec_open2(codec_context, codec, nullptr) < 0)
+	{
+		avcodec_free_context(&codec_context);
+		throw VideoDecoderException("Failed to open codec context");
+	}
 }
 
 VideoDecoder::~VideoDecoder()
 {
 	avcodec_close(codec_context);
-	avcodec_free_context(&codec_context); // TODO: does close by itself too?
-	// TODO: free codec?
+	avcodec_free_context(&codec_context);
 }
 
 void VideoDecoder::PushFrame(uint8_t *buf, size_t buf_size)
@@ -48,12 +53,42 @@ void VideoDecoder::PushFrame(uint8_t *buf, size_t buf_size)
 		av_init_packet(&packet);
 		packet.data = buf;
 		packet.size = buf_size;
-		avcodec_send_packet(codec_context, &packet);
+		int r;
+send_packet:
+		r = avcodec_send_packet(codec_context, &packet);
+		if(r != 0)
+		{
+			if(r == AVERROR(EAGAIN))
+			{
+				printf("avcodec internal buffer is full, removing frames\n"); // TODO: log to somewhere else
+				AVFrame *frame = av_frame_alloc();
+				if(!frame)
+				{
+					printf("failed to alloc frame\n");
+					return;
+				}
+				r = avcodec_receive_frame(codec_context, frame);
+				av_frame_free(&frame);
+				if(r != 0)
+				{
+					printf("failed to pull packet\n");
+					return;
+				}
+				goto send_packet;
+			}
+			else
+			{
+				printf("failed to push frame\n");
+				return;
+			}
+		}
 	}
 
 	emit FramesAvailable();
 }
 
+#include <unistd.h>
+
 AVFrame *VideoDecoder::PullFrame()
 {
 	QMutexLocker locker(&mutex);