| // Copyright 2011 Google Inc. All Rights Reserved. |
| // |
| // Use of this source code is governed by a BSD-style license |
| // that can be found in the COPYING file in the root of the source |
| // tree. An additional intellectual property rights grant can be found |
| // in the file PATENTS. All contributing project authors may |
| // be found in the AUTHORS file in the root of the source tree. |
| // ----------------------------------------------------------------------------- |
| // |
| // SSE2 version of YUV to RGB upsampling functions. |
| // |
| // Author: somnath@google.com (Somnath Banerjee) |
| |
| #include "./dsp.h" |
| |
| #if defined(WEBP_USE_SSE2) |
| |
| #include <assert.h> |
| #include <emmintrin.h> |
| #include <string.h> |
| #include "./yuv.h" |
| |
| #ifdef FANCY_UPSAMPLING |
| |
| // We compute (9*a + 3*b + 3*c + d + 8) / 16 as follows |
| // u = (9*a + 3*b + 3*c + d + 8) / 16 |
| // = (a + (a + 3*b + 3*c + d) / 8 + 1) / 2 |
| // = (a + m + 1) / 2 |
| // where m = (a + 3*b + 3*c + d) / 8 |
| // = ((a + b + c + d) / 2 + b + c) / 4 |
| // |
| // Let's say k = (a + b + c + d) / 4. |
| // We can compute k as |
| // k = (s + t + 1) / 2 - ((a^d) | (b^c) | (s^t)) & 1 |
| // where s = (a + d + 1) / 2 and t = (b + c + 1) / 2 |
| // |
| // Then m can be written as |
| // m = (k + t + 1) / 2 - (((b^c) & (s^t)) | (k^t)) & 1 |
| |
| // Computes out = (k + in + 1) / 2 - ((ij & (s^t)) | (k^in)) & 1 |
| #define GET_M(ij, in, out) do { \ |
| const __m128i tmp0 = _mm_avg_epu8(k, (in)); /* (k + in + 1) / 2 */ \ |
| const __m128i tmp1 = _mm_and_si128((ij), st); /* (ij) & (s^t) */ \ |
| const __m128i tmp2 = _mm_xor_si128(k, (in)); /* (k^in) */ \ |
| const __m128i tmp3 = _mm_or_si128(tmp1, tmp2); /* ((ij) & (s^t)) | (k^in) */\ |
| const __m128i tmp4 = _mm_and_si128(tmp3, one); /* & 1 -> lsb_correction */ \ |
| (out) = _mm_sub_epi8(tmp0, tmp4); /* (k + in + 1) / 2 - lsb_correction */ \ |
| } while (0) |
| |
| // pack and store two alternating pixel rows |
| #define PACK_AND_STORE(a, b, da, db, out) do { \ |
| const __m128i t_a = _mm_avg_epu8(a, da); /* (9a + 3b + 3c + d + 8) / 16 */ \ |
| const __m128i t_b = _mm_avg_epu8(b, db); /* (3a + 9b + c + 3d + 8) / 16 */ \ |
| const __m128i t_1 = _mm_unpacklo_epi8(t_a, t_b); \ |
| const __m128i t_2 = _mm_unpackhi_epi8(t_a, t_b); \ |
| _mm_store_si128(((__m128i*)(out)) + 0, t_1); \ |
| _mm_store_si128(((__m128i*)(out)) + 1, t_2); \ |
| } while (0) |
| |
| // Loads 17 pixels each from rows r1 and r2 and generates 32 pixels. |
| #define UPSAMPLE_32PIXELS(r1, r2, out) { \ |
| const __m128i one = _mm_set1_epi8(1); \ |
| const __m128i a = _mm_loadu_si128((__m128i*)&(r1)[0]); \ |
| const __m128i b = _mm_loadu_si128((__m128i*)&(r1)[1]); \ |
| const __m128i c = _mm_loadu_si128((__m128i*)&(r2)[0]); \ |
| const __m128i d = _mm_loadu_si128((__m128i*)&(r2)[1]); \ |
| \ |
| const __m128i s = _mm_avg_epu8(a, d); /* s = (a + d + 1) / 2 */ \ |
| const __m128i t = _mm_avg_epu8(b, c); /* t = (b + c + 1) / 2 */ \ |
| const __m128i st = _mm_xor_si128(s, t); /* st = s^t */ \ |
| \ |
| const __m128i ad = _mm_xor_si128(a, d); /* ad = a^d */ \ |
| const __m128i bc = _mm_xor_si128(b, c); /* bc = b^c */ \ |
| \ |
| const __m128i t1 = _mm_or_si128(ad, bc); /* (a^d) | (b^c) */ \ |
| const __m128i t2 = _mm_or_si128(t1, st); /* (a^d) | (b^c) | (s^t) */ \ |
| const __m128i t3 = _mm_and_si128(t2, one); /* (a^d) | (b^c) | (s^t) & 1 */ \ |
| const __m128i t4 = _mm_avg_epu8(s, t); \ |
| const __m128i k = _mm_sub_epi8(t4, t3); /* k = (a + b + c + d) / 4 */ \ |
| __m128i diag1, diag2; \ |
| \ |
| GET_M(bc, t, diag1); /* diag1 = (a + 3b + 3c + d) / 8 */ \ |
| GET_M(ad, s, diag2); /* diag2 = (3a + b + c + 3d) / 8 */ \ |
| \ |
| /* pack the alternate pixels */ \ |
| PACK_AND_STORE(a, b, diag1, diag2, out + 0); /* store top */ \ |
| PACK_AND_STORE(c, d, diag2, diag1, out + 2 * 32); /* store bottom */ \ |
| } |
| |
| // Turn the macro into a function for reducing code-size when non-critical |
| static void Upsample32Pixels(const uint8_t r1[], const uint8_t r2[], |
| uint8_t* const out) { |
| UPSAMPLE_32PIXELS(r1, r2, out); |
| } |
| |
| #define UPSAMPLE_LAST_BLOCK(tb, bb, num_pixels, out) { \ |
| uint8_t r1[17], r2[17]; \ |
| memcpy(r1, (tb), (num_pixels)); \ |
| memcpy(r2, (bb), (num_pixels)); \ |
| /* replicate last byte */ \ |
| memset(r1 + (num_pixels), r1[(num_pixels) - 1], 17 - (num_pixels)); \ |
| memset(r2 + (num_pixels), r2[(num_pixels) - 1], 17 - (num_pixels)); \ |
| /* using the shared function instead of the macro saves ~3k code size */ \ |
| Upsample32Pixels(r1, r2, out); \ |
| } |
| |
| #define CONVERT2RGB(FUNC, XSTEP, top_y, bottom_y, \ |
| top_dst, bottom_dst, cur_x, num_pixels) { \ |
| int n; \ |
| for (n = 0; n < (num_pixels); ++n) { \ |
| FUNC(top_y[(cur_x) + n], r_u[n], r_v[n], \ |
| top_dst + ((cur_x) + n) * XSTEP); \ |
| } \ |
| if (bottom_y != NULL) { \ |
| for (n = 0; n < (num_pixels); ++n) { \ |
| FUNC(bottom_y[(cur_x) + n], r_u[64 + n], r_v[64 + n], \ |
| bottom_dst + ((cur_x) + n) * XSTEP); \ |
| } \ |
| } \ |
| } |
| |
| #define CONVERT2RGB_32(FUNC, XSTEP, top_y, bottom_y, \ |
| top_dst, bottom_dst, cur_x) do { \ |
| FUNC##32(top_y + (cur_x), r_u, r_v, top_dst + (cur_x) * XSTEP); \ |
| if (bottom_y != NULL) { \ |
| FUNC##32(bottom_y + (cur_x), r_u + 64, r_v + 64, \ |
| bottom_dst + (cur_x) * XSTEP); \ |
| } \ |
| } while (0) |
| |
| #define SSE2_UPSAMPLE_FUNC(FUNC_NAME, FUNC, XSTEP) \ |
| static void FUNC_NAME(const uint8_t* top_y, const uint8_t* bottom_y, \ |
| const uint8_t* top_u, const uint8_t* top_v, \ |
| const uint8_t* cur_u, const uint8_t* cur_v, \ |
| uint8_t* top_dst, uint8_t* bottom_dst, int len) { \ |
| int uv_pos, pos; \ |
| /* 16byte-aligned array to cache reconstructed u and v */ \ |
| uint8_t uv_buf[4 * 32 + 15]; \ |
| uint8_t* const r_u = (uint8_t*)((uintptr_t)(uv_buf + 15) & ~15); \ |
| uint8_t* const r_v = r_u + 32; \ |
| \ |
| assert(top_y != NULL); \ |
| { /* Treat the first pixel in regular way */ \ |
| const int u_diag = ((top_u[0] + cur_u[0]) >> 1) + 1; \ |
| const int v_diag = ((top_v[0] + cur_v[0]) >> 1) + 1; \ |
| const int u0_t = (top_u[0] + u_diag) >> 1; \ |
| const int v0_t = (top_v[0] + v_diag) >> 1; \ |
| FUNC(top_y[0], u0_t, v0_t, top_dst); \ |
| if (bottom_y != NULL) { \ |
| const int u0_b = (cur_u[0] + u_diag) >> 1; \ |
| const int v0_b = (cur_v[0] + v_diag) >> 1; \ |
| FUNC(bottom_y[0], u0_b, v0_b, bottom_dst); \ |
| } \ |
| } \ |
| /* For UPSAMPLE_32PIXELS, 17 u/v values must be read-able for each block */ \ |
| for (pos = 1, uv_pos = 0; pos + 32 + 1 <= len; pos += 32, uv_pos += 16) { \ |
| UPSAMPLE_32PIXELS(top_u + uv_pos, cur_u + uv_pos, r_u); \ |
| UPSAMPLE_32PIXELS(top_v + uv_pos, cur_v + uv_pos, r_v); \ |
| CONVERT2RGB_32(FUNC, XSTEP, top_y, bottom_y, top_dst, bottom_dst, pos); \ |
| } \ |
| if (len > 1) { \ |
| const int left_over = ((len + 1) >> 1) - (pos >> 1); \ |
| assert(left_over > 0); \ |
| UPSAMPLE_LAST_BLOCK(top_u + uv_pos, cur_u + uv_pos, left_over, r_u); \ |
| UPSAMPLE_LAST_BLOCK(top_v + uv_pos, cur_v + uv_pos, left_over, r_v); \ |
| CONVERT2RGB(FUNC, XSTEP, top_y, bottom_y, top_dst, bottom_dst, \ |
| pos, len - pos); \ |
| } \ |
| } |
| |
| // SSE2 variants of the fancy upsampler. |
| SSE2_UPSAMPLE_FUNC(UpsampleRgbLinePair, VP8YuvToRgb, 3) |
| SSE2_UPSAMPLE_FUNC(UpsampleBgrLinePair, VP8YuvToBgr, 3) |
| SSE2_UPSAMPLE_FUNC(UpsampleRgbaLinePair, VP8YuvToRgba, 4) |
| SSE2_UPSAMPLE_FUNC(UpsampleBgraLinePair, VP8YuvToBgra, 4) |
| |
| #undef GET_M |
| #undef PACK_AND_STORE |
| #undef UPSAMPLE_32PIXELS |
| #undef UPSAMPLE_LAST_BLOCK |
| #undef CONVERT2RGB |
| #undef CONVERT2RGB_32 |
| #undef SSE2_UPSAMPLE_FUNC |
| |
| #endif // FANCY_UPSAMPLING |
| |
| #endif // WEBP_USE_SSE2 |
| |
| //------------------------------------------------------------------------------ |
| |
| extern void WebPInitUpsamplersSSE2(void); |
| |
| #ifdef FANCY_UPSAMPLING |
| |
| extern WebPUpsampleLinePairFunc WebPUpsamplers[/* MODE_LAST */]; |
| |
| void WebPInitUpsamplersSSE2(void) { |
| #if defined(WEBP_USE_SSE2) |
| VP8YUVInitSSE2(); |
| WebPUpsamplers[MODE_RGB] = UpsampleRgbLinePair; |
| WebPUpsamplers[MODE_RGBA] = UpsampleRgbaLinePair; |
| WebPUpsamplers[MODE_BGR] = UpsampleBgrLinePair; |
| WebPUpsamplers[MODE_BGRA] = UpsampleBgraLinePair; |
| WebPUpsamplers[MODE_rgbA] = UpsampleRgbaLinePair; |
| WebPUpsamplers[MODE_bgrA] = UpsampleBgraLinePair; |
| #endif // WEBP_USE_SSE2 |
| } |
| |
| #else |
| |
| // this empty function is to avoid an empty .o |
| void WebPInitUpsamplersSSE2(void) {} |
| |
| #endif // FANCY_UPSAMPLING |
