OpenGlContext and Threads

General JUCE discussion
21

This is from a few years ago, hopefully it still works!

(It does make assumptions on pixel order, using PixelRGB would be a much better, but hopefully it gives you a start)

if(img_convert_ctx == NULL) {
                                int w = outputWidth;
                                int h = outputHeight;
                                
                                img_convert_ctx = sws_getContext(w, h, 
                                                                 pCodecCtx->pix_fmt, 
                                                                 w, h, OUTPUTFORMAT, SWS_BILINEAR, // SWS_BICUBIC  -- doesn't take aspect into consideration...
                                                                 NULL, NULL, NULL);
                                if(img_convert_ctx == NULL) {
                                    fprintf(stderr, "Cannot initialize the conversion context!\n");
                                    exit(1);
                                }
                            }
                            
                            // put into RGB Frame...
                            
                            int ret = sws_scale(img_convert_ctx,  (const uint8_t* const*)pFrame->data, pFrame->linesize, 0, 
                                                outputHeight, pFrameRGB->data, pFrameRGB->linesize);
                            jassert(ret>0);
                            
                            Image anImage(Image::ARGB,outputWidth, outputHeight,false);
                            Image::BitmapData bmData(anImage,0,0,outputWidth, outputHeight,Image::BitmapData::readWrite);
                            
                            for(int y=0; y<outputHeight; y++)
                            {
                                uint8* juceImage=bmData.getLinePointer(y);
                                uint8* srcPtr=pFrameRGB->data[0]+y*pFrameRGB->linesize[0];
                                for (int x=0;x<outputWidth;x++)
                                {
#if JUCE_BIG_ENDIAN
                                    // argb
                                    juceImage[0]=0xff;
                                    juceImage[1]=srcPtr[0];
                                    juceImage[2]=srcPtr[1];
                                    juceImage[3]=srcPtr[2];
#else
                                    // bgra
                                    juceImage[0]=srcPtr[2];
                                    juceImage[1]=srcPtr[1];
                                    juceImage[2]=srcPtr[0];
                                    juceImage[3]=0xff;
#endif
                                    juceImage +=bmData.pixelStride;
                                    srcPtr+=3;
                                }
                                
                            }