Question:
AMcap is a app for capturing video or to preview from webcam. Its source code comes with Microsoft Windows SDK as sample.
I want to (bypass the following process of user interaction in amcap code or say want to) set it as default:
Ampcap menu
Options Video Capture Pin ... Color Space/Compression: YUY2 Output size: 1600x1200 I have a compatible webcam and works fine on changing manually to YUY2 and 1600x1200 in AMcap app.
By default it is:
Color Space/Compression: MJPG Output size: 160x120 I tried to find 'YUY2' string in whole project, but I could not find it, so that I could hardcode it. It seems it is created dynamically and then operated; refer: in the file amcap.cpp nearby line no 3395.
Solution:1
I have some code that uses an IID_IAMStreamConfig interface to set the camera image size. I didn't use it to set the image format, but I added the code that I think will do the job. It is untested however.
// get the number of formats and make sure the strutucre size matches int count; int size; VIDEO_STREAM_CONFIG_CAPS caps; pSC->GetNumberOfCapabilities(&count, &size); if( sizeof(caps) != size ) { // Error } AM_MEDIA_TYPE* mt_p = NULL; hr = pSC->GetStreamCaps(0, &mt_p, (BYTE*)&caps); if (hr != S_OK) { // Error } if ((mt_p->majortype != MEDIATYPE_Video) || (mt_p->formattype != FORMAT_VideoInfo)) { // Error } VIDEOINFOHEADER* video_info_header_p = (VIDEOINFOHEADER *)mt_p->pbFormat; video_info_header_p->bmiHeader.biWidth = 1600; video_info_header_p->bmiHeader.biHeight = 1200; // Code to change video format // I think 16 is the right value for biBitCount, but I am not sure!!!! video_info_header_p->bmiHeader.biCompression = MAKEFOURCC('Y','U','Y','2'); video_info_header_p->bmiHeader.biBitCount = 16; hr = pSC->SetFormat(mt_p); if (hr != S_OK) { // Error } if (mt_p->cbFormat != 0) { CoTaskMemFree((PVOID)mt_p->pbFormat); mt_p->cbFormat = 0; mt_p->pbFormat = NULL; } if (mt_p->pUnk != NULL) { // Unecessary because pUnk should not be used, but safest. mt_p->pUnk->Release(); mt_p->pUnk = NULL; } You should place the code after the following block in amcap:
if(hr != NOERROR) hr = gcap.pBuilder->FindInterface(&PIN_CATEGORY_CAPTURE, &MEDIATYPE_Video, gcap.pVCap, IID_IAMStreamConfig, (void **)&pSC); Again, this is untested code, but you can try it and I hope it helps.
Solution:2
Hey @Dani van der Meer: Thanks for the Pointer ... I have done it by: In the function BOOL InitCapFilters()
after
if(hr != NOERROR) { hr = gcap.pBuilder->FindInterface(&PIN_CATEGORY_CAPTURE, &MEDIATYPE_Video, gcap.pVCap, IID_IAMStreamConfig, (void **)&gcap.pVSC); if(hr != NOERROR) { // this means we can't set frame rate (non-DV only) ErrMsg(TEXT("Error %x: Cannot find VCapture:IAMStreamConfig"), hr); } } gcap.fCapAudioIsRelevant = TRUE; Paste:
CMediaType *pmt; // default capture format if(gcap.pVSC && gcap.pVSC->GetFormat((AM_MEDIA_TYPE**)&pmt) == S_OK) { // DV capture does not use a VIDEOINFOHEADER if(pmt->formattype == FORMAT_VideoInfo) { pmt->SetType(&MEDIATYPE_Video); pmt->SetFormatType(&FORMAT_VideoInfo); pmt->SetSubtype(&MEDIASUBTYPE_YUY2); pmt->SetTemporalCompression(FALSE); VIDEOINFOHEADER* lpvihin = (VIDEOINFOHEADER*) pmt->pbFormat; { //DWORD fccYUY2 = 'YUY2' ; //lpvihin->bmiHeader.biCompression =fccYUY2; //'YUY2';// MAKEFOURCC('Y','U','Y','2'); //lpvihin->bmiHeader.biBitCount = 16; lpvihin->bmiHeader.biWidth = 1600;// 960; //1600; lpvihin->bmiHeader.biHeight = 1200;// 720; //1200; lpvihin->bmiHeader.biSizeImage = 1600*1200*3; hr = gcap.pVSC->SetFormat(pmt); ResizeWindow(HEADER(pmt->pbFormat)->biWidth, ABS(HEADER(pmt->pbFormat)->biHeight)); } } if(pmt->majortype != MEDIATYPE_Video) { // This capture filter captures something other that pure video. // Maybe it's DV or something? Anyway, chances are we shouldn't // allow capturing audio separately, since our video capture // filter may have audio combined in it already! gcap.fCapAudioIsRelevant = FALSE; gcap.fCapAudio = FALSE; } DeleteMediaType(pmt); } Thanks a lot
Note:If u also have question or solution just comment us below or mail us on toontricks1994@gmail.com
EmoticonEmoticon