Video Converter: FAQ

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This is the FAQ page for the Video Converter DirectShow filter.


What CPU extensions are used?

We use MMX, SSE and SSE2 extensions with auto detection of supported features.

What is precision used?

Integer base algorithm.

How to use programmatically only those resize methods that I need?

You can set them via via IVideoConverter2::SetConversionProps2().

How do I use the Video Converter to downscale HD material to SD?

For this purpose you need to specify the CONVERTER_PROPS2 structure:

::ZeroMemory( &cnvProps2, sizeof(cnvProps2) );
// Or eVCI_Field1First, eVCI_Field2First, eVCI_Progressive for manual setting of interlace:
cnvProps.eInterlaceIn = eVCI_Auto; 
cnvProps.nAspectIn = 0; // For use VideoInfoHeader2 flags or e.g. MAKELPARAM( 16, 9 ) for 16:9 AR.
cnvProps.eInterlaceIn = eVCI_Auto; // Or eVCI_Field1First, eVCI_Field2First, eVCI_Progressive for manual setting of interlace. = 720; = 576;
cnvProps.nAspectOut = MAKELPARAM( 4, 3 );
cnvProps.eKeepAspect2 = eVCKA_LetterBox; // Or eVCKA_Crop for crop or eVCKA_None for not maintain AR.
cnvProps.eResize = eVCR_CubicWithMP; // See eVCResize for other interplation algorithms.
cnvProps.eFieldProcess = eVCFP_Auto; // See eVCFieldProcess for other options.
cnvProps.optimization = eThreadPerProc; // Or eOneThread - for work in 'sync' mode.
cnvProps.dwUseCPUMask = -1; // Use all available cores/CPUs.
int nMask = VC_ALL_MASK;
cpVideConverter->SetConversionProps2( &cnvProps, &nMask );

What are the possible output parameters of the CONVERTER_PROPS2 struct (i.e. the posible values of the fccOutput parameter)?

typedef enum eMGFCC
                eMGFCC_Default    = 0,        // The default value - usual the same as input 
                eMGFCC_YV12   = 0x32315659,
                eMGFCC_I420   = 0x30323449,
                eMGFCC_YUY2   = 0x32595559,
                eMGFCC_UYVY   = 0x59565955,
                eMGFCC_YVYU   = 0x55595659,
                eMGFCC_HDYC   = 0x43594448,   // DeckLink fourcc for HD video (CCIR 709) - similar to UYVY (CCIR 601)
                eMGFCC_RGB24  = 0xe436eb7d,
                eMGFCC_RGB32  = 0xe436eb7e,
                eMGFCC_ARGB32 = 0x773c9ac0,
        } eMGFCC;
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