recreatePreviewNode

gistfile1.txt

bool VapourSynthScriptProcessor::recreatePreviewNode(NodePair & a_nodePair)
{
	if(!a_nodePair.pOutputNode)
		return false;

	if(!m_cpVSAPI)
		return false;

	if(a_nodePair.pPreviewNode)
	{
		m_cpVSAPI->freeNode(a_nodePair.pPreviewNode);
		a_nodePair.pPreviewNode = nullptr;
	}

	const VSVideoInfo * cpVideoInfo =
		m_cpVSAPI->getVideoInfo(a_nodePair.pOutputNode);
	if(!cpVideoInfo)
		return false;
	const VSFormat * cpFormat = cpVideoInfo->format;

	if(cpFormat->id == pfCompatBGR32)
	{
		a_nodePair.pPreviewNode =
			m_cpVSAPI->cloneNodeRef(a_nodePair.pOutputNode);
		return true;
	}

	bool isYUV = ((cpFormat->colorFamily == cmYUV) ||
		(cpFormat->id == pfCompatYUY2));
	bool canSubsample = (isYUV || (cpFormat->colorFamily == cmYCoCg));

	VSCore * pCore = m_pVSScriptLibrary->getCore(m_pVSScript);
	VSPlugin * pResizePlugin = m_cpVSAPI->getPluginById(
		"com.vapoursynth.resize", pCore);
	const char * resizeName = "Point";

	VSMap * pArgumentMap = m_cpVSAPI->createMap();
	m_cpVSAPI->propSetNode(pArgumentMap, "clip", a_nodePair.pOutputNode,
		paReplace);
	m_cpVSAPI->propSetInt(pArgumentMap, "format", pfCompatBGR32, paReplace);

	if(canSubsample)
	{
		switch(m_chromaResamplingFilter)
		{
		case ResamplingFilter::Point:
			resizeName = "Point";
			break;
		case ResamplingFilter::Bilinear:
			resizeName = "Bilinear";
			break;
		case ResamplingFilter::Bicubic:
			resizeName = "Bicubic";
			m_cpVSAPI->propSetFloat(pArgumentMap, "filter_param_a_uv",
				m_resamplingFilterParameterA, paReplace);
			m_cpVSAPI->propSetFloat(pArgumentMap, "filter_param_b_uv",
				m_resamplingFilterParameterB, paReplace);
			break;
		case ResamplingFilter::Lanczos:
			resizeName = "Lanczos";
			m_cpVSAPI->propSetFloat(pArgumentMap, "filter_param_a_uv",
				m_resamplingFilterParameterA, paReplace);
			break;
		case ResamplingFilter::Spline16:
			resizeName = "Spline16";
			break;
		case ResamplingFilter::Spline36:
			resizeName = "Spline36";
			break;
		default:
			assert(false);
		}
	}

	m_cpVSAPI->propSetInt(pArgumentMap, "prefer_props", 1, paReplace);

	if(isYUV)
	{
		const char * matrixInS = nullptr;
		switch(m_yuvMatrix)
		{
		case YuvMatrixCoefficients::m709:
			matrixInS = "709";
			break;
		case YuvMatrixCoefficients::m470BG:
			matrixInS = "470bg";
			break;
		case YuvMatrixCoefficients::m170M:
			matrixInS = "170m";
			break;
		case YuvMatrixCoefficients::m2020_NCL:
			matrixInS = "2020ncl";
			break;
		case YuvMatrixCoefficients::m2020_CL:
			matrixInS = "2020cl";
			break;
		default:
			assert(false);
		}

		int matrixStringLength = (int)strlen(matrixInS);
		m_cpVSAPI->propSetData(pArgumentMap, "matrix_in_s",
			matrixInS, matrixStringLength, paReplace);

		if(m_yuvMatrix == YuvMatrixCoefficients::m2020_CL)
		{
			const char * transferIn = "709";
			const char * transferOut = "2020_10";

			m_cpVSAPI->propSetData(pArgumentMap, "transfer_in_s",
				transferIn, (int)strlen(transferIn), paReplace);
			m_cpVSAPI->propSetData(pArgumentMap, "transfer_s",
				transferOut, (int)strlen(transferOut), paReplace);
		}
	}

	if(canSubsample)
	{
		int64_t chromaLoc = 0;
		switch(m_chromaPlacement)
		{
		case ChromaPlacement::MPEG1:
			chromaLoc = 1;
			break;
		case ChromaPlacement::MPEG2:
			chromaLoc = 0;
			break;
		case ChromaPlacement::DV:
			chromaLoc = 2;
			break;
		default:
			assert(false);
		}
		m_cpVSAPI->propSetInt(pArgumentMap, "chromaloc",
			chromaLoc, paReplace);
	}

	VSMap * pResultMap = m_cpVSAPI->invoke(pResizePlugin, resizeName,
		pArgumentMap);

	m_cpVSAPI->freeMap(pArgumentMap);

	const char * cpResultError = m_cpVSAPI->getError(pResultMap);

	if(cpResultError)
	{
		m_error = trUtf8("Failed to convert to RGB:\n");
		m_error += cpResultError;
		emit signalWriteLogMessage(mtCritical, m_error);
		m_cpVSAPI->freeMap(pResultMap);
		return false;
	}

	VSNodeRef * pPreviewNode = m_cpVSAPI->propGetNode(pResultMap, "clip", 0,
		nullptr);
	assert(pPreviewNode);
	a_nodePair.pPreviewNode = pPreviewNode;

	m_cpVSAPI->freeMap(pResultMap);

	return true;
}