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");
}
}