使用快速指令集来将YUV转成32位RGB

yuv420_to_argb8888.c

void yuv420_to_argb8888(uint8_t *pYUV,
    uint32_t sy, uint32_t suv,
    int width, int height,
    uint32_t *rgb, uint32_t srgb) {
    uint8_t *yp;
    uint8_t *up;
    uint8_t *vp;
    yp = pYUV;
    up = pYUV + width*height;
    vp = up + width*height / 4;

    __m128i y0r0, y0r1, u0, v0;
    __m128i y00r0, y01r0, y00r1, y01r1;
    __m128i u00, u01, v00, v01;
    __m128i rv00, rv01, gu00, gu01, gv00, gv01, bu00, bu01;
    __m128i r00, r01, g00, g01, b00, b01;
    __m128i rgb0123, rgb4567, rgb89ab, rgbcdef;
    __m128i gbgb;
    __m128i ysub, uvsub;
    __m128i zero, facy, facrv, facgu, facgv, facbu;
    __m128i *srcy128r0, *srcy128r1;
    __m128i *dstrgb128r0, *dstrgb128r1;
    __m64   *srcu64, *srcv64;
    int x, y;

    ysub = _mm_set1_epi32(0x00100010);
    uvsub = _mm_set1_epi32(0x00800080);

    facy = _mm_set1_epi32(0x004a004a);
    facrv = _mm_set1_epi32(0x00660066);
    facgu = _mm_set1_epi32(0x00190019);
    facgv = _mm_set1_epi32(0x00340034);
    facbu = _mm_set1_epi32(0x00810081);

    zero = _mm_set1_epi32(0x00000000);

    for (y = 0; y < height; y += 2) {

        srcy128r0 = (__m128i *)(yp + sy*y);
        srcy128r1 = (__m128i *)(yp + sy*y + sy);
        srcu64 = (__m64 *)(up + suv*(y / 2));
        srcv64 = (__m64 *)(vp + suv*(y / 2));

        dstrgb128r0 = (__m128i *)(rgb + srgb*y);
        dstrgb128r1 = (__m128i *)(rgb + srgb*y + srgb);

        for (x = 0; x < width; x += 16) {

            u0 = _mm_loadl_epi64((__m128i *)srcu64); srcu64++;
            v0 = _mm_loadl_epi64((__m128i *)srcv64); srcv64++;

            y0r0 = _mm_loadu_si128(srcy128r0++);
            y0r1 = _mm_loadu_si128(srcy128r1++);

            // constant y factors
            y00r0 = _mm_mullo_epi16(_mm_sub_epi16(_mm_unpacklo_epi8(y0r0, zero), ysub), facy);
            y01r0 = _mm_mullo_epi16(_mm_sub_epi16(_mm_unpackhi_epi8(y0r0, zero), ysub), facy);
            y00r1 = _mm_mullo_epi16(_mm_sub_epi16(_mm_unpacklo_epi8(y0r1, zero), ysub), facy);
            y01r1 = _mm_mullo_epi16(_mm_sub_epi16(_mm_unpackhi_epi8(y0r1, zero), ysub), facy);

            // expand u and v so they're aligned with y values
            u0 = _mm_unpacklo_epi8(u0, zero);
            u00 = _mm_sub_epi16(_mm_unpacklo_epi16(u0, u0), uvsub);
            u01 = _mm_sub_epi16(_mm_unpackhi_epi16(u0, u0), uvsub);

            v0 = _mm_unpacklo_epi8(v0, zero);
            v00 = _mm_sub_epi16(_mm_unpacklo_epi16(v0, v0), uvsub);
            v01 = _mm_sub_epi16(_mm_unpackhi_epi16(v0, v0), uvsub);

            // common factors on both rows.
            rv00 = _mm_mullo_epi16(facrv, v00);
            rv01 = _mm_mullo_epi16(facrv, v01);
            gu00 = _mm_mullo_epi16(facgu, u00);
            gu01 = _mm_mullo_epi16(facgu, u01);
            gv00 = _mm_mullo_epi16(facgv, v00);
            gv01 = _mm_mullo_epi16(facgv, v01);
            bu00 = _mm_mullo_epi16(facbu, u00);
            bu01 = _mm_mullo_epi16(facbu, u01);

            // row 0
            r00 = _mm_srai_epi16(_mm_add_epi16(y00r0, rv00), 6);
            r01 = _mm_srai_epi16(_mm_add_epi16(y01r0, rv01), 6);
            g00 = _mm_srai_epi16(_mm_sub_epi16(_mm_sub_epi16(y00r0, gu00), gv00), 6);
            g01 = _mm_srai_epi16(_mm_sub_epi16(_mm_sub_epi16(y01r0, gu01), gv01), 6);
            b00 = _mm_srai_epi16(_mm_add_epi16(y00r0, bu00), 6);
            b01 = _mm_srai_epi16(_mm_add_epi16(y01r0, bu01), 6);

            r00 = _mm_packus_epi16(r00, r01);         // rrrr.. saturated
            g00 = _mm_packus_epi16(g00, g01);         // gggg.. saturated
            b00 = _mm_packus_epi16(b00, b01);         // bbbb.. saturated


            r01 = _mm_unpacklo_epi8(b00, zero); // 0r0r..
            gbgb = _mm_unpacklo_epi8(r00, g00);  // gbgb..
            rgb0123 = _mm_unpacklo_epi16(gbgb, r01);  // 0rgb0rgb..
            rgb4567 = _mm_unpackhi_epi16(gbgb, r01);  // 0rgb0rgb..

            r01 = _mm_unpackhi_epi8(b00, zero);
            gbgb = _mm_unpackhi_epi8(r00, g00);
            rgb89ab = _mm_unpacklo_epi16(gbgb, r01);
            rgbcdef = _mm_unpackhi_epi16(gbgb, r01);

            _mm_storeu_si128(dstrgb128r0++, rgb0123);
            _mm_storeu_si128(dstrgb128r0++, rgb4567);
            _mm_storeu_si128(dstrgb128r0++, rgb89ab);
            _mm_storeu_si128(dstrgb128r0++, rgbcdef);

            // row 1
            r00 = _mm_srai_epi16(_mm_add_epi16(y00r1, rv00), 6);
            r01 = _mm_srai_epi16(_mm_add_epi16(y01r1, rv01), 6);
            g00 = _mm_srai_epi16(_mm_sub_epi16(_mm_sub_epi16(y00r1, gu00), gv00), 6);
            g01 = _mm_srai_epi16(_mm_sub_epi16(_mm_sub_epi16(y01r1, gu01), gv01), 6);
            b00 = _mm_srai_epi16(_mm_add_epi16(y00r1, bu00), 6);
            b01 = _mm_srai_epi16(_mm_add_epi16(y01r1, bu01), 6);

            r00 = _mm_packus_epi16(r00, r01);         // rrrr.. saturated
            g00 = _mm_packus_epi16(g00, g01);         // gggg.. saturated
            b00 = _mm_packus_epi16(b00, b01);         // bbbb.. saturated


            r01 = _mm_unpacklo_epi8(b00, zero); // 0r0r..
            gbgb = _mm_unpacklo_epi8(r00, g00);  // gbgb..
            rgb0123 = _mm_unpacklo_epi16(gbgb, r01);  // 0rgb0rgb..
            rgb4567 = _mm_unpackhi_epi16(gbgb, r01);  // 0rgb0rgb..

            r01 = _mm_unpackhi_epi8(b00, zero);
            gbgb = _mm_unpackhi_epi8(r00, g00);
            rgb89ab = _mm_unpacklo_epi16(gbgb, r01);
            rgbcdef = _mm_unpackhi_epi16(gbgb, r01);

            _mm_storeu_si128(dstrgb128r1++, rgb0123);
            _mm_storeu_si128(dstrgb128r1++, rgb4567);
            _mm_storeu_si128(dstrgb128r1++, rgb89ab);
            _mm_storeu_si128(dstrgb128r1++, rgbcdef);

        }
    }
}