- for (int ty = start_ty, oy = start_oy; ty < size().height && oy < other->size().height; ++ty, ++oy) {
- uint8_t* tp = data()[0] + ty * stride()[0] + start_tx * this_bpp;
- uint8_t* op = other->data()[0] + oy * other->stride()[0];
- for (int tx = start_tx, ox = start_ox; tx < size().width && ox < other->size().width; ++tx, ++ox) {
- float const alpha = float (op[3]) / 255;
- tp[0] = op[0] + (tp[0] * (1 - alpha));
- tp[1] = op[1] + (tp[1] * (1 - alpha));
- tp[2] = op[2] + (tp[2] * (1 - alpha));
- tp[3] = op[3] + (tp[3] * (1 - alpha));
-
- tp += this_bpp;
- op += other_bpp;
+ switch (_pixel_format) {
+ case AV_PIX_FMT_RGB24:
+ {
+ /* Going onto RGB24. First byte is red, second green, third blue */
+ int const this_bpp = 3;
+ for (int ty = start_ty, oy = start_oy; ty < size().height && oy < other->size().height; ++ty, ++oy) {
+ uint8_t* tp = data()[0] + ty * stride()[0] + start_tx * this_bpp;
+ uint8_t* op = other->data()[0] + oy * other->stride()[0];
+ for (int tx = start_tx, ox = start_ox; tx < size().width && ox < other->size().width; ++tx, ++ox) {
+ float const alpha = float (op[3]) / 255;
+ tp[0] = op[2] * alpha + tp[0] * (1 - alpha);
+ tp[1] = op[1] * alpha + tp[1] * (1 - alpha);
+ tp[2] = op[0] * alpha + tp[2] * (1 - alpha);
+
+ tp += this_bpp;
+ op += other_bpp;
+ }
+ }
+ break;
+ }
+ case AV_PIX_FMT_BGRA:
+ case AV_PIX_FMT_RGBA:
+ {
+ int const this_bpp = 4;
+ for (int ty = start_ty, oy = start_oy; ty < size().height && oy < other->size().height; ++ty, ++oy) {
+ uint8_t* tp = data()[0] + ty * stride()[0] + start_tx * this_bpp;
+ uint8_t* op = other->data()[0] + oy * other->stride()[0];
+ for (int tx = start_tx, ox = start_ox; tx < size().width && ox < other->size().width; ++tx, ++ox) {
+ float const alpha = float (op[3]) / 255;
+ tp[0] = op[0] * alpha + tp[0] * (1 - alpha);
+ tp[1] = op[1] * alpha + tp[1] * (1 - alpha);
+ tp[2] = op[2] * alpha + tp[2] * (1 - alpha);
+ tp[3] = op[3] * alpha + tp[3] * (1 - alpha);
+
+ tp += this_bpp;
+ op += other_bpp;
+ }
+ }
+ break;
+ }
+ case AV_PIX_FMT_RGB48LE:
+ {
+ int const this_bpp = 6;
+ for (int ty = start_ty, oy = start_oy; ty < size().height && oy < other->size().height; ++ty, ++oy) {
+ uint8_t* tp = data()[0] + ty * stride()[0] + start_tx * this_bpp;
+ uint8_t* op = other->data()[0] + oy * other->stride()[0];
+ for (int tx = start_tx, ox = start_ox; tx < size().width && ox < other->size().width; ++tx, ++ox) {
+ float const alpha = float (op[3]) / 255;
+ /* Blend high bytes; the RGBA in op appears to be BGRA */
+ tp[1] = op[2] * alpha + tp[1] * (1 - alpha);
+ tp[3] = op[1] * alpha + tp[3] * (1 - alpha);
+ tp[5] = op[0] * alpha + tp[5] * (1 - alpha);
+
+ tp += this_bpp;
+ op += other_bpp;
+ }
+ }
+ break;
+ }
+ case AV_PIX_FMT_XYZ12LE:
+ {
+ boost::numeric::ublas::matrix<double> matrix = dcp::ColourConversion::srgb_to_xyz().rgb_to_xyz();
+ int const this_bpp = 6;
+ for (int ty = start_ty, oy = start_oy; ty < size().height && oy < other->size().height; ++ty, ++oy) {
+ uint8_t* tp = data()[0] + ty * stride()[0] + start_tx * this_bpp;
+ uint8_t* op = other->data()[0] + oy * other->stride()[0];
+ for (int tx = start_tx, ox = start_ox; tx < size().width && ox < other->size().width; ++tx, ++ox) {
+ float const alpha = float (op[3]) / 255;
+
+ /* Convert sRGB to XYZ; op is BGRA */
+ int const x = matrix(0, 0) * op[2] + matrix(0, 1) * op[1] + matrix(0, 2) * op[0];
+ int const y = matrix(1, 0) * op[2] + matrix(1, 1) * op[1] + matrix(1, 2) * op[0];
+ int const z = matrix(2, 0) * op[2] + matrix(2, 1) * op[1] + matrix(2, 2) * op[0];
+
+ /* Blend high bytes */
+ tp[1] = min (x, 255) * alpha + tp[1] * (1 - alpha);
+ tp[3] = min (y, 255) * alpha + tp[3] * (1 - alpha);
+ tp[5] = min (z, 255) * alpha + tp[5] * (1 - alpha);
+
+ tp += this_bpp;
+ op += other_bpp;
+ }