// // Created by xu fulong on 2022/7/9. // #include "yuv_converter.h" #include // https://chromium.googlesource.com/libyuv/libyuv // https://mymusing.co/bt601-yuv-to-rgb-conversion-color/ // https://www.color.org/chardata/rgb/rgb_registry.xalter // BT.601 YUV to RGB // R = 1.164 * (Y - 16) + 1.596 * (V - 128) // G = 1.164 * (Y - 16) - 0.392 * (U - 128) - 0.812 * (V - 128) // B = 1.164 * (Y - 16) + 2.016 * (U - 128) // Y = 0.257 * R + 0.504 * G + 0.098 * B + 16 // U = -0.148 * R - 0.291 * G + 0.439 * B + 128 // V = 0.439 * R - 0.368 * G - 0.072 * B + 128 // BT.709 YUV to RGB // R = 1.1644 * (Y - 16) + 1.7928 * (V - 128) // G = 1.1644 * (Y - 16) - 0.2133 * (U - 128) - 0.533 * (V - 128) // B = 1.1644 * (Y - 16) + 2.1124 * (U - 128) // Y = 0.1826 * R + 0.6142 * G + 0.0620 * B + 16 // U = -0.1006 * R - 0.3386 * G + 0.4392 * B + 128 // V = 0.4392 * B - 0.3989 * G - 0.0403 * B + 128 // BT.2020 YUV to RGB // R = Y - 16 + 1.4746 * (V - 128) // G = Y - 16 - 0.1645 * (U - 128) - 0.5713 * (V - 128) // B = Y - 16 + 1.881 * (U - 128) // Y = 0.2627 * R + 0.6780 * G + 0.0593 * B + 16 // U = -0.1396 * R - 0.3604 * G + 0.5 * B + 128 // V = 0.5 * R - 0.4598 * G - 0.0402 * B + 128 static void rgba_to_yuv420p(int *argb, int8_t *yuv, int width, int height) { int frameSize = width * height; int index = 0; int yIndex = 0; int uIndex = frameSize; int vIndex = frameSize * 5 / 4; int R, G, B, Y, U, V; for (int j = 0; j < height; j++) { for (int i = 0; i < width; i++) { R = (argb[index] & 0xff0000) >> 16; G = (argb[index] & 0xff00) >> 8; B = (argb[index] & 0xff); // RGB to YUV algorithm Y = ((66 * R + 129 * G + 25 * B + 128) >> 8) + 16; // I420(YUV420p) -> YYYYYYYY UU VV yuv[yIndex++] = (int8_t) Y; if (j % 2 == 0 && i % 2 == 0) { U = ((-38 * R - 74 * G + 112 * B + 128) >> 8) + 128; V = ((112 * R - 94 * G - 18 * B + 128) >> 8) + 128; yuv[uIndex++] = (int8_t) U; yuv[vIndex++] = (int8_t) V; } index++; } } } static int yuv2argb(int y, int u, int v) { #define max(a, b) ((a) > (b) ? (a) : (b)) int r, g, b; r = y + (int) (1.402f * u); g = y - (int) (0.344f * v + 0.714f * u); b = y + (int) (1.772f * v); r = r > 255 ? 255 : max(r, 0); g = g > 255 ? 255 : max(g, 0); b = b > 255 ? 255 : max(b, 0); return 0xff000000 | (r << 16) | (g << 8) | b; } static void yuv420p_to_argb(int8_t *yuv, int *argb, int width, int height) { int size = width * height; int offset = size; int u, v, y1, y2, y3, y4; for (int i = 0, k = 0; i < size; i += 2, k += 2) { y1 = yuv[i] & 0xff; y2 = yuv[i + 1] & 0xff; y3 = yuv[width + i] & 0xff; y4 = yuv[width + i + 1] & 0xff; u = yuv[offset + k] & 0xff; v = yuv[offset + k + 1] & 0xff; u = u - 128; v = v - 128; argb[i] = yuv2argb(y1, u, v); argb[i + 1] = yuv2argb(y2, u, v); argb[width + i] = yuv2argb(y3, u, v); argb[width + i + 1] = yuv2argb(y4, u, v); if (i != 0 && (i + 2) % width == 0) i += width; } } static void nv21_to_yuv420p(int8_t *dst, int8_t *src, int len) { memcpy(dst, src, len); // y for (int i = 0; i < len / 4; ++i) { *(dst + len + i) = *(src + len + i * 2 + 1); // u *(dst + len * 5 / 4 + i) = *(src + len + i * 2); // v } } static void yuv420p_rotate90(int8_t *dst, int8_t *src, int width, int height) { int n = 0; int wh = width * height; int half_width = width / 2; int half_height = height / 2; // y for (int j = 0; j < width; j++) { for (int i = height - 1; i >= 0; i--) { dst[n++] = src[width * i + j]; } } // u for (int i = 0; i < half_width; i++) { for (int j = 1; j <= half_height; j++) { dst[n++] = src[wh + ((half_height - j) * half_width + i)]; } } // v for (int i = 0; i < half_width; i++) { for (int j = 1; j <= half_height; j++) { dst[n++] = src[wh + wh / 4 + ((half_height - j) * half_width + i)]; } } } static void yuv420p_rotate180(int8_t *dst, int8_t *src, int width, int height) { int n = 0; int half_width = width / 2; int half_height = height / 2; // y for (int j = height - 1; j >= 0; j--) { for (int i = width; i > 0; i--) { dst[n++] = src[width * j + i - 1]; } } // u int offset = width * height; for (int j = half_height - 1; j >= 0; j--) { for (int i = half_width; i > 0; i--) { dst[n++] = src[offset + half_width * j + i - 1]; } } // v offset += half_width * half_height; for (int j = half_height - 1; j >= 0; j--) { for (int i = half_width; i > 0; i--) { dst[n++] = src[offset + half_width * j + i - 1]; } } } static void yuv420p_rotate270(int8_t *dst, int8_t *src, int width, int height) { for (int j = 0; j < width; j++) { for (int i = 1; i <= height; i++) { *dest++ = *(src + i * width - j); } } char *src_u = src + width * height; for (int j = 0; j < width / 2; j++) { for (int i = 1; i <= height / 2; i++) { *dest++ = *(src_u + i * width / 2 - j); } } char *src_v = src + width * height * 5 / 4; for (int j = 0; j < width / 2; j++) { for (int i = 1; i <= height / 2; i++) { *dest++ = *(src_v + i * width / 2 - j); } } } static void yuv420p_rotate(int8_t *dst, int8_t *src, int width, int height, int degree) { switch(degree) { case 0: memcpy(dst, src, width * height * 3 / 2); break; case 90: yuv420p_rotate90(dst, src, width, height); break; case 180: yuv420p_rotate180(dst, src, width, height); break; case 270: yuv420p_rotate270(dst, src, width, height); break; default: break; } }