Configuring Image Streams
[The feature associated with this page, Windows Media Format 11 SDK, is a legacy feature. It has been superseded by Source Reader and Sink Writer. Source Reader and Sink Writer have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Source Reader and Sink Writer instead of Windows Media Format 11 SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
Image streams contain still images in JPEG format. Even though image streams are like video streams in that they take uncompressed images as inputs, they require a slightly different configuration. To configure an image stream, you must set the values for the members of the video configuration structures as shown in the following table.
| Setting | Description |
|---|---|
| WM_MEDIA_TYPE.majortype | Set to WMMEDIATYPE_Image. |
| WM_MEDIA_TYPE.subtype | Set to WMMEDIASUBTYPE_RGB24. |
| WM_MEDIA_TYPE.bFixedSizeSamples | Set to FALSE. |
| WM_MEDIA_TYPE.bTemporalCompression | Set to FALSE. |
| WM_MEDIA_TYPE.lSampleSize | Set to 0. |
| WM_MEDIA_TYPE.formattype | Set to WMFORMAT_VideoInfo. |
| WM_MEDIA_TYPE.pUnk | Set to NULL. |
| WM_MEDIA_TYPE.cbFormat | Set to sizeof(WMVIDEOINFOHEADER). |
| WM_MEDIA_TYPE.pbFormat | Set to the address of a properly configured WMVIDEOINFOHEADER structure. |
| WMVIDEOINFOHEADER.rcSource and WMVIDEOINFOHEADER.rcTarget | Set both rectangles so that the top left corners are coordinates (0, 0) and the bottom right corners are coordinates(x, y) where x is the image width and y is the image height. |
| WMVIDEOINFOHEADER.dwBitRate | Set to the bit rate of the stream. |
| WMVIDEOINFOHEADER.dwErrorRate | Set to 0. |
| WMVIDEOINFOHEADER.dwBitErrorRate | Set to 0. |
| WMVIDEOINFOHEADER.AvgTimePerFrame | Set to 0. |
| BITMAPINFOHEADER.biWidth | Set to the width of the image. |
| BITMAPINFOHEADER.biHeight | Set to the height of the image. |
| BITMAPINFOHEADER.biPlanes | Set to 1. |
| BITMAPINFOHEADER.biBitCount | Set to 24. |
| BITMAPINFOHEADER.biCompression | Set to BI_RGB. |
| BITMAPINFOHEADER.biSizeImage | Set to ((x * y * c) / 8), where x is the width of the image, y is the height of the image, and c is the color depth of the image (in this case always 24). |
| BITMAPINFOHEADER.biXPelsPerMeter | Set to 0. |
| BITMAPINFOHEADER.biYPelsPerMeter | Set to 0. |
| BITMAPINFOHEADER.biClrUsed | Set to 0. |
| BITMAPINFOHEADER.biClrImportant | Set to 0. |
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