Beispiel #1
0
        private void recreateCodecContext()
        {
            if (stream == null)
            {
                return;
            }

            var  codecParams    = *stream->codecpar;
            bool openSuccessful = false;

            foreach (var(decoder, hwDeviceType) in GetAvailableDecoders(formatContext->iformat, codecParams.codec_id, TargetHardwareVideoDecoders.Value))
            {
                // free context in case it was allocated in a previous iteration or recreate call.
                if (codecContext != null)
                {
                    fixed(AVCodecContext **ptr = &codecContext)
                    ffmpeg.avcodec_free_context(ptr);
                }

                codecContext = ffmpeg.avcodec_alloc_context3(decoder.Pointer);
                codecContext->pkt_timebase = stream->time_base;

                if (codecContext == null)
                {
                    Logger.Log($"Couldn't allocate codec context. Codec: {decoder.Name}");
                    continue;
                }

                int paramCopyResult = ffmpeg.avcodec_parameters_to_context(codecContext, &codecParams);

                if (paramCopyResult < 0)
                {
                    Logger.Log($"Couldn't copy codec parameters from {decoder.Name}: {getErrorMessage(paramCopyResult)}");
                    continue;
                }

                // initialize hardware decode context.
                if (hwDeviceType != AVHWDeviceType.AV_HWDEVICE_TYPE_NONE)
                {
                    int hwDeviceCreateResult = ffmpeg.av_hwdevice_ctx_create(&codecContext->hw_device_ctx, hwDeviceType, null, null, 0);

                    if (hwDeviceCreateResult < 0)
                    {
                        Logger.Log($"Couldn't create hardware video decoder context {hwDeviceType} for codec {decoder.Name}: {getErrorMessage(hwDeviceCreateResult)}");
                        continue;
                    }

                    Logger.Log($"Successfully opened hardware video decoder context {hwDeviceType} for codec {decoder.Name}");
                }

                int openCodecResult = ffmpeg.avcodec_open2(codecContext, decoder.Pointer, null);

                if (openCodecResult < 0)
                {
                    Logger.Log($"Error trying to open {decoder.Name} codec: {getErrorMessage(openCodecResult)}");
                    continue;
                }

                Logger.Log($"Successfully initialized decoder: {decoder.Name}");

                openSuccessful = true;
                break;
            }

            if (!openSuccessful)
            {
                throw new InvalidOperationException("No usable decoder found");
            }
        }