/* * Copyright (c) 2016, Alliance for Open Media. All rights reserved. * * This source code is subject to the terms of the BSD 2 Clause License and * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License * was not distributed with this source code in the LICENSE file, you can * obtain it at www.aomedia.org/license/software. If the Alliance for Open * Media Patent License 1.0 was not distributed with this source code in the * PATENTS file, you can obtain it at www.aomedia.org/license/patent. */ #include #include #include #include #include #include "config/av1_rtcd.h" #include "av1/common/av1_common_int.h" #include "av1/common/warped_motion.h" #include "av1/common/scale.h" // For warping, we really use a 6-tap filter, but we do blocks of 8 pixels // at a time. The zoom/rotation/shear in the model are applied to the // "fractional" position of each pixel, which therefore varies within // [-1, 2) * WARPEDPIXEL_PREC_SHIFTS. // We need an extra 2 taps to fit this in, for a total of 8 taps. /* clang-format off */ const int16_t av1_warped_filter[WARPEDPIXEL_PREC_SHIFTS * 3 + 1][8] = { // [-1, 0) { 0, 0, 127, 1, 0, 0, 0, 0 }, { 0, - 1, 127, 2, 0, 0, 0, 0 }, { 1, - 3, 127, 4, - 1, 0, 0, 0 }, { 1, - 4, 126, 6, - 2, 1, 0, 0 }, { 1, - 5, 126, 8, - 3, 1, 0, 0 }, { 1, - 6, 125, 11, - 4, 1, 0, 0 }, { 1, - 7, 124, 13, - 4, 1, 0, 0 }, { 2, - 8, 123, 15, - 5, 1, 0, 0 }, { 2, - 9, 122, 18, - 6, 1, 0, 0 }, { 2, -10, 121, 20, - 6, 1, 0, 0 }, { 2, -11, 120, 22, - 7, 2, 0, 0 }, { 2, -12, 119, 25, - 8, 2, 0, 0 }, { 3, -13, 117, 27, - 8, 2, 0, 0 }, { 3, -13, 116, 29, - 9, 2, 0, 0 }, { 3, -14, 114, 32, -10, 3, 0, 0 }, { 3, -15, 113, 35, -10, 2, 0, 0 }, { 3, -15, 111, 37, -11, 3, 0, 0 }, { 3, -16, 109, 40, -11, 3, 0, 0 }, { 3, -16, 108, 42, -12, 3, 0, 0 }, { 4, -17, 106, 45, -13, 3, 0, 0 }, { 4, -17, 104, 47, -13, 3, 0, 0 }, { 4, -17, 102, 50, -14, 3, 0, 0 }, { 4, -17, 100, 52, -14, 3, 0, 0 }, { 4, -18, 98, 55, -15, 4, 0, 0 }, { 4, -18, 96, 58, -15, 3, 0, 0 }, { 4, -18, 94, 60, -16, 4, 0, 0 }, { 4, -18, 91, 63, -16, 4, 0, 0 }, { 4, -18, 89, 65, -16, 4, 0, 0 }, { 4, -18, 87, 68, -17, 4, 0, 0 }, { 4, -18, 85, 70, -17, 4, 0, 0 }, { 4, -18, 82, 73, -17, 4, 0, 0 }, { 4, -18, 80, 75, -17, 4, 0, 0 }, { 4, -18, 78, 78, -18, 4, 0, 0 }, { 4, -17, 75, 80, -18, 4, 0, 0 }, { 4, -17, 73, 82, -18, 4, 0, 0 }, { 4, -17, 70, 85, -18, 4, 0, 0 }, { 4, -17, 68, 87, -18, 4, 0, 0 }, { 4, -16, 65, 89, -18, 4, 0, 0 }, { 4, -16, 63, 91, -18, 4, 0, 0 }, { 4, -16, 60, 94, -18, 4, 0, 0 }, { 3, -15, 58, 96, -18, 4, 0, 0 }, { 4, -15, 55, 98, -18, 4, 0, 0 }, { 3, -14, 52, 100, -17, 4, 0, 0 }, { 3, -14, 50, 102, -17, 4, 0, 0 }, { 3, -13, 47, 104, -17, 4, 0, 0 }, { 3, -13, 45, 106, -17, 4, 0, 0 }, { 3, -12, 42, 108, -16, 3, 0, 0 }, { 3, -11, 40, 109, -16, 3, 0, 0 }, { 3, -11, 37, 111, -15, 3, 0, 0 }, { 2, -10, 35, 113, -15, 3, 0, 0 }, { 3, -10, 32, 114, -14, 3, 0, 0 }, { 2, - 9, 29, 116, -13, 3, 0, 0 }, { 2, - 8, 27, 117, -13, 3, 0, 0 }, { 2, - 8, 25, 119, -12, 2, 0, 0 }, { 2, - 7, 22, 120, -11, 2, 0, 0 }, { 1, - 6, 20, 121, -10, 2, 0, 0 }, { 1, - 6, 18, 122, - 9, 2, 0, 0 }, { 1, - 5, 15, 123, - 8, 2, 0, 0 }, { 1, - 4, 13, 124, - 7, 1, 0, 0 }, { 1, - 4, 11, 125, - 6, 1, 0, 0 }, { 1, - 3, 8, 126, - 5, 1, 0, 0 }, { 1, - 2, 6, 126, - 4, 1, 0, 0 }, { 0, - 1, 4, 127, - 3, 1, 0, 0 }, { 0, 0, 2, 127, - 1, 0, 0, 0 }, // [0, 1) { 0, 0, 0, 127, 1, 0, 0, 0}, { 0, 0, -1, 127, 2, 0, 0, 0}, { 0, 1, -3, 127, 4, -2, 1, 0}, { 0, 1, -5, 127, 6, -2, 1, 0}, { 0, 2, -6, 126, 8, -3, 1, 0}, {-1, 2, -7, 126, 11, -4, 2, -1}, {-1, 3, -8, 125, 13, -5, 2, -1}, {-1, 3, -10, 124, 16, -6, 3, -1}, {-1, 4, -11, 123, 18, -7, 3, -1}, {-1, 4, -12, 122, 20, -7, 3, -1}, {-1, 4, -13, 121, 23, -8, 3, -1}, {-2, 5, -14, 120, 25, -9, 4, -1}, {-1, 5, -15, 119, 27, -10, 4, -1}, {-1, 5, -16, 118, 30, -11, 4, -1}, {-2, 6, -17, 116, 33, -12, 5, -1}, {-2, 6, -17, 114, 35, -12, 5, -1}, {-2, 6, -18, 113, 38, -13, 5, -1}, {-2, 7, -19, 111, 41, -14, 6, -2}, {-2, 7, -19, 110, 43, -15, 6, -2}, {-2, 7, -20, 108, 46, -15, 6, -2}, {-2, 7, -20, 106, 49, -16, 6, -2}, {-2, 7, -21, 104, 51, -16, 7, -2}, {-2, 7, -21, 102, 54, -17, 7, -2}, {-2, 8, -21, 100, 56, -18, 7, -2}, {-2, 8, -22, 98, 59, -18, 7, -2}, {-2, 8, -22, 96, 62, -19, 7, -2}, {-2, 8, -22, 94, 64, -19, 7, -2}, {-2, 8, -22, 91, 67, -20, 8, -2}, {-2, 8, -22, 89, 69, -20, 8, -2}, {-2, 8, -22, 87, 72, -21, 8, -2}, {-2, 8, -21, 84, 74, -21, 8, -2}, {-2, 8, -22, 82, 77, -21, 8, -2}, {-2, 8, -21, 79, 79, -21, 8, -2}, {-2, 8, -21, 77, 82, -22, 8, -2}, {-2, 8, -21, 74, 84, -21, 8, -2}, {-2, 8, -21, 72, 87, -22, 8, -2}, {-2, 8, -20, 69, 89, -22, 8, -2}, {-2, 8, -20, 67, 91, -22, 8, -2}, {-2, 7, -19, 64, 94, -22, 8, -2}, {-2, 7, -19, 62, 96, -22, 8, -2}, {-2, 7, -18, 59, 98, -22, 8, -2}, {-2, 7, -18, 56, 100, -21, 8, -2}, {-2, 7, -17, 54, 102, -21, 7, -2}, {-2, 7, -16, 51, 104, -21, 7, -2}, {-2, 6, -16, 49, 106, -20, 7, -2}, {-2, 6, -15, 46, 108, -20, 7, -2}, {-2, 6, -15, 43, 110, -19, 7, -2}, {-2, 6, -14, 41, 111, -19, 7, -2}, {-1, 5, -13, 38, 113, -18, 6, -2}, {-1, 5, -12, 35, 114, -17, 6, -2}, {-1, 5, -12, 33, 116, -17, 6, -2}, {-1, 4, -11, 30, 118, -16, 5, -1}, {-1, 4, -10, 27, 119, -15, 5, -1}, {-1, 4, -9, 25, 120, -14, 5, -2}, {-1, 3, -8, 23, 121, -13, 4, -1}, {-1, 3, -7, 20, 122, -12, 4, -1}, {-1, 3, -7, 18, 123, -11, 4, -1}, {-1, 3, -6, 16, 124, -10, 3, -1}, {-1, 2, -5, 13, 125, -8, 3, -1}, {-1, 2, -4, 11, 126, -7, 2, -1}, { 0, 1, -3, 8, 126, -6, 2, 0}, { 0, 1, -2, 6, 127, -5, 1, 0}, { 0, 1, -2, 4, 127, -3, 1, 0}, { 0, 0, 0, 2, 127, -1, 0, 0}, // [1, 2) { 0, 0, 0, 1, 127, 0, 0, 0 }, { 0, 0, 0, - 1, 127, 2, 0, 0 }, { 0, 0, 1, - 3, 127, 4, - 1, 0 }, { 0, 0, 1, - 4, 126, 6, - 2, 1 }, { 0, 0, 1, - 5, 126, 8, - 3, 1 }, { 0, 0, 1, - 6, 125, 11, - 4, 1 }, { 0, 0, 1, - 7, 124, 13, - 4, 1 }, { 0, 0, 2, - 8, 123, 15, - 5, 1 }, { 0, 0, 2, - 9, 122, 18, - 6, 1 }, { 0, 0, 2, -10, 121, 20, - 6, 1 }, { 0, 0, 2, -11, 120, 22, - 7, 2 }, { 0, 0, 2, -12, 119, 25, - 8, 2 }, { 0, 0, 3, -13, 117, 27, - 8, 2 }, { 0, 0, 3, -13, 116, 29, - 9, 2 }, { 0, 0, 3, -14, 114, 32, -10, 3 }, { 0, 0, 3, -15, 113, 35, -10, 2 }, { 0, 0, 3, -15, 111, 37, -11, 3 }, { 0, 0, 3, -16, 109, 40, -11, 3 }, { 0, 0, 3, -16, 108, 42, -12, 3 }, { 0, 0, 4, -17, 106, 45, -13, 3 }, { 0, 0, 4, -17, 104, 47, -13, 3 }, { 0, 0, 4, -17, 102, 50, -14, 3 }, { 0, 0, 4, -17, 100, 52, -14, 3 }, { 0, 0, 4, -18, 98, 55, -15, 4 }, { 0, 0, 4, -18, 96, 58, -15, 3 }, { 0, 0, 4, -18, 94, 60, -16, 4 }, { 0, 0, 4, -18, 91, 63, -16, 4 }, { 0, 0, 4, -18, 89, 65, -16, 4 }, { 0, 0, 4, -18, 87, 68, -17, 4 }, { 0, 0, 4, -18, 85, 70, -17, 4 }, { 0, 0, 4, -18, 82, 73, -17, 4 }, { 0, 0, 4, -18, 80, 75, -17, 4 }, { 0, 0, 4, -18, 78, 78, -18, 4 }, { 0, 0, 4, -17, 75, 80, -18, 4 }, { 0, 0, 4, -17, 73, 82, -18, 4 }, { 0, 0, 4, -17, 70, 85, -18, 4 }, { 0, 0, 4, -17, 68, 87, -18, 4 }, { 0, 0, 4, -16, 65, 89, -18, 4 }, { 0, 0, 4, -16, 63, 91, -18, 4 }, { 0, 0, 4, -16, 60, 94, -18, 4 }, { 0, 0, 3, -15, 58, 96, -18, 4 }, { 0, 0, 4, -15, 55, 98, -18, 4 }, { 0, 0, 3, -14, 52, 100, -17, 4 }, { 0, 0, 3, -14, 50, 102, -17, 4 }, { 0, 0, 3, -13, 47, 104, -17, 4 }, { 0, 0, 3, -13, 45, 106, -17, 4 }, { 0, 0, 3, -12, 42, 108, -16, 3 }, { 0, 0, 3, -11, 40, 109, -16, 3 }, { 0, 0, 3, -11, 37, 111, -15, 3 }, { 0, 0, 2, -10, 35, 113, -15, 3 }, { 0, 0, 3, -10, 32, 114, -14, 3 }, { 0, 0, 2, - 9, 29, 116, -13, 3 }, { 0, 0, 2, - 8, 27, 117, -13, 3 }, { 0, 0, 2, - 8, 25, 119, -12, 2 }, { 0, 0, 2, - 7, 22, 120, -11, 2 }, { 0, 0, 1, - 6, 20, 121, -10, 2 }, { 0, 0, 1, - 6, 18, 122, - 9, 2 }, { 0, 0, 1, - 5, 15, 123, - 8, 2 }, { 0, 0, 1, - 4, 13, 124, - 7, 1 }, { 0, 0, 1, - 4, 11, 125, - 6, 1 }, { 0, 0, 1, - 3, 8, 126, - 5, 1 }, { 0, 0, 1, - 2, 6, 126, - 4, 1 }, { 0, 0, 0, - 1, 4, 127, - 3, 1 }, { 0, 0, 0, 0, 2, 127, - 1, 0 }, // dummy (replicate row index 191) { 0, 0, 0, 0, 2, 127, - 1, 0 }, }; /* clang-format on */ #define DIV_LUT_PREC_BITS 14 #define DIV_LUT_BITS 8 #define DIV_LUT_NUM (1 << DIV_LUT_BITS) static const uint16_t div_lut[DIV_LUT_NUM + 1] = { 16384, 16320, 16257, 16194, 16132, 16070, 16009, 15948, 15888, 15828, 15768, 15709, 15650, 15592, 15534, 15477, 15420, 15364, 15308, 15252, 15197, 15142, 15087, 15033, 14980, 14926, 14873, 14821, 14769, 14717, 14665, 14614, 14564, 14513, 14463, 14413, 14364, 14315, 14266, 14218, 14170, 14122, 14075, 14028, 13981, 13935, 13888, 13843, 13797, 13752, 13707, 13662, 13618, 13574, 13530, 13487, 13443, 13400, 13358, 13315, 13273, 13231, 13190, 13148, 13107, 13066, 13026, 12985, 12945, 12906, 12866, 12827, 12788, 12749, 12710, 12672, 12633, 12596, 12558, 12520, 12483, 12446, 12409, 12373, 12336, 12300, 12264, 12228, 12193, 12157, 12122, 12087, 12053, 12018, 11984, 11950, 11916, 11882, 11848, 11815, 11782, 11749, 11716, 11683, 11651, 11619, 11586, 11555, 11523, 11491, 11460, 11429, 11398, 11367, 11336, 11305, 11275, 11245, 11215, 11185, 11155, 11125, 11096, 11067, 11038, 11009, 10980, 10951, 10923, 10894, 10866, 10838, 10810, 10782, 10755, 10727, 10700, 10673, 10645, 10618, 10592, 10565, 10538, 10512, 10486, 10460, 10434, 10408, 10382, 10356, 10331, 10305, 10280, 10255, 10230, 10205, 10180, 10156, 10131, 10107, 10082, 10058, 10034, 10010, 9986, 9963, 9939, 9916, 9892, 9869, 9846, 9823, 9800, 9777, 9754, 9732, 9709, 9687, 9664, 9642, 9620, 9598, 9576, 9554, 9533, 9511, 9489, 9468, 9447, 9425, 9404, 9383, 9362, 9341, 9321, 9300, 9279, 9259, 9239, 9218, 9198, 9178, 9158, 9138, 9118, 9098, 9079, 9059, 9039, 9020, 9001, 8981, 8962, 8943, 8924, 8905, 8886, 8867, 8849, 8830, 8812, 8793, 8775, 8756, 8738, 8720, 8702, 8684, 8666, 8648, 8630, 8613, 8595, 8577, 8560, 8542, 8525, 8508, 8490, 8473, 8456, 8439, 8422, 8405, 8389, 8372, 8355, 8339, 8322, 8306, 8289, 8273, 8257, 8240, 8224, 8208, 8192, }; // Decomposes a divisor D such that 1/D = y/2^shift, where y is returned // at precision of DIV_LUT_PREC_BITS along with the shift. static int16_t resolve_divisor_64(uint64_t D, int16_t *shift) { int64_t f; *shift = (int16_t)((D >> 32) ? get_msb((unsigned int)(D >> 32)) + 32 : get_msb((unsigned int)D)); // e is obtained from D after resetting the most significant 1 bit. const int64_t e = D - ((uint64_t)1 << *shift); // Get the most significant DIV_LUT_BITS (8) bits of e into f if (*shift > DIV_LUT_BITS) f = ROUND_POWER_OF_TWO_64(e, *shift - DIV_LUT_BITS); else f = e << (DIV_LUT_BITS - *shift); assert(f <= DIV_LUT_NUM); *shift += DIV_LUT_PREC_BITS; // Use f as lookup into the precomputed table of multipliers return div_lut[f]; } static int16_t resolve_divisor_32(uint32_t D, int16_t *shift) { int32_t f; *shift = get_msb(D); // e is obtained from D after resetting the most significant 1 bit. const int32_t e = D - ((uint32_t)1 << *shift); // Get the most significant DIV_LUT_BITS (8) bits of e into f if (*shift > DIV_LUT_BITS) f = ROUND_POWER_OF_TWO(e, *shift - DIV_LUT_BITS); else f = e << (DIV_LUT_BITS - *shift); assert(f <= DIV_LUT_NUM); *shift += DIV_LUT_PREC_BITS; // Use f as lookup into the precomputed table of multipliers return div_lut[f]; } static int is_affine_valid(const WarpedMotionParams *const wm) { const int32_t *mat = wm->wmmat; return (mat[2] > 0); } static int is_affine_shear_allowed(int16_t alpha, int16_t beta, int16_t gamma, int16_t delta) { if ((4 * abs(alpha) + 7 * abs(beta) >= (1 << WARPEDMODEL_PREC_BITS)) || (4 * abs(gamma) + 4 * abs(delta) >= (1 << WARPEDMODEL_PREC_BITS))) return 0; else return 1; } #ifndef NDEBUG // Check that the given warp model satisfies the relevant constraints for // its stated model type static void check_model_consistency(WarpedMotionParams *wm) { switch (wm->wmtype) { case IDENTITY: assert(wm->wmmat[0] == 0); assert(wm->wmmat[1] == 0); AOM_FALLTHROUGH_INTENDED; case TRANSLATION: assert(wm->wmmat[2] == 1 << WARPEDMODEL_PREC_BITS); assert(wm->wmmat[3] == 0); AOM_FALLTHROUGH_INTENDED; case ROTZOOM: assert(wm->wmmat[4] == -wm->wmmat[3]); assert(wm->wmmat[5] == wm->wmmat[2]); AOM_FALLTHROUGH_INTENDED; case AFFINE: break; default: assert(0 && "Bad wmtype"); } } #endif // NDEBUG // Returns 1 on success or 0 on an invalid affine set int av1_get_shear_params(WarpedMotionParams *wm) { #ifndef NDEBUG // Check that models have been constructed sensibly // This is a good place to check, because this function does not need to // be called until after model construction is complete, but must be called // before the model can be used for prediction. check_model_consistency(wm); #endif // NDEBUG const int32_t *mat = wm->wmmat; if (!is_affine_valid(wm)) return 0; wm->alpha = clamp(mat[2] - (1 << WARPEDMODEL_PREC_BITS), INT16_MIN, INT16_MAX); wm->beta = clamp(mat[3], INT16_MIN, INT16_MAX); int16_t shift; int16_t y = resolve_divisor_32(abs(mat[2]), &shift) * (mat[2] < 0 ? -1 : 1); int64_t v = ((int64_t)mat[4] * (1 << WARPEDMODEL_PREC_BITS)) * y; wm->gamma = clamp((int)ROUND_POWER_OF_TWO_SIGNED_64(v, shift), INT16_MIN, INT16_MAX); v = ((int64_t)mat[3] * mat[4]) * y; wm->delta = clamp(mat[5] - (int)ROUND_POWER_OF_TWO_SIGNED_64(v, shift) - (1 << WARPEDMODEL_PREC_BITS), INT16_MIN, INT16_MAX); wm->alpha = ROUND_POWER_OF_TWO_SIGNED(wm->alpha, WARP_PARAM_REDUCE_BITS) * (1 << WARP_PARAM_REDUCE_BITS); wm->beta = ROUND_POWER_OF_TWO_SIGNED(wm->beta, WARP_PARAM_REDUCE_BITS) * (1 << WARP_PARAM_REDUCE_BITS); wm->gamma = ROUND_POWER_OF_TWO_SIGNED(wm->gamma, WARP_PARAM_REDUCE_BITS) * (1 << WARP_PARAM_REDUCE_BITS); wm->delta = ROUND_POWER_OF_TWO_SIGNED(wm->delta, WARP_PARAM_REDUCE_BITS) * (1 << WARP_PARAM_REDUCE_BITS); if (!is_affine_shear_allowed(wm->alpha, wm->beta, wm->gamma, wm->delta)) return 0; return 1; } #if CONFIG_AV1_HIGHBITDEPTH /* Note: For an explanation of the warp algorithm, and some notes on bit widths for hardware implementations, see the comments above av1_warp_affine_c */ void av1_highbd_warp_affine_c(const int32_t *mat, const uint16_t *ref, int width, int height, int stride, uint16_t *pred, int p_col, int p_row, int p_width, int p_height, int p_stride, int subsampling_x, int subsampling_y, int bd, ConvolveParams *conv_params, int16_t alpha, int16_t beta, int16_t gamma, int16_t delta) { int32_t tmp[15 * 8]; const int reduce_bits_horiz = conv_params->round_0; const int reduce_bits_vert = conv_params->is_compound ? conv_params->round_1 : 2 * FILTER_BITS - reduce_bits_horiz; const int max_bits_horiz = bd + FILTER_BITS + 1 - reduce_bits_horiz; const int offset_bits_horiz = bd + FILTER_BITS - 1; const int offset_bits_vert = bd + 2 * FILTER_BITS - reduce_bits_horiz; const int round_bits = 2 * FILTER_BITS - conv_params->round_0 - conv_params->round_1; const int offset_bits = bd + 2 * FILTER_BITS - conv_params->round_0; (void)max_bits_horiz; assert(IMPLIES(conv_params->is_compound, conv_params->dst != NULL)); // Check that, even with 12-bit input, the intermediate values will fit // into an unsigned 16-bit intermediate array. assert(bd + FILTER_BITS + 2 - conv_params->round_0 <= 16); for (int i = p_row; i < p_row + p_height; i += 8) { for (int j = p_col; j < p_col + p_width; j += 8) { // Calculate the center of this 8x8 block, // project to luma coordinates (if in a subsampled chroma plane), // apply the affine transformation, // then convert back to the original coordinates (if necessary) const int32_t src_x = (j + 4) << subsampling_x; const int32_t src_y = (i + 4) << subsampling_y; const int64_t dst_x = (int64_t)mat[2] * src_x + (int64_t)mat[3] * src_y + (int64_t)mat[0]; const int64_t dst_y = (int64_t)mat[4] * src_x + (int64_t)mat[5] * src_y + (int64_t)mat[1]; const int64_t x4 = dst_x >> subsampling_x; const int64_t y4 = dst_y >> subsampling_y; const int32_t ix4 = (int32_t)(x4 >> WARPEDMODEL_PREC_BITS); int32_t sx4 = x4 & ((1 << WARPEDMODEL_PREC_BITS) - 1); const int32_t iy4 = (int32_t)(y4 >> WARPEDMODEL_PREC_BITS); int32_t sy4 = y4 & ((1 << WARPEDMODEL_PREC_BITS) - 1); sx4 += alpha * (-4) + beta * (-4); sy4 += gamma * (-4) + delta * (-4); sx4 &= ~((1 << WARP_PARAM_REDUCE_BITS) - 1); sy4 &= ~((1 << WARP_PARAM_REDUCE_BITS) - 1); // Horizontal filter for (int k = -7; k < 8; ++k) { const int iy = clamp(iy4 + k, 0, height - 1); int sx = sx4 + beta * (k + 4); for (int l = -4; l < 4; ++l) { int ix = ix4 + l - 3; const int offs = ROUND_POWER_OF_TWO(sx, WARPEDDIFF_PREC_BITS) + WARPEDPIXEL_PREC_SHIFTS; assert(offs >= 0 && offs <= WARPEDPIXEL_PREC_SHIFTS * 3); const int16_t *coeffs = av1_warped_filter[offs]; int32_t sum = 1 << offset_bits_horiz; for (int m = 0; m < 8; ++m) { const int sample_x = clamp(ix + m, 0, width - 1); sum += ref[iy * stride + sample_x] * coeffs[m]; } sum = ROUND_POWER_OF_TWO(sum, reduce_bits_horiz); assert(0 <= sum && sum < (1 << max_bits_horiz)); tmp[(k + 7) * 8 + (l + 4)] = sum; sx += alpha; } } // Vertical filter for (int k = -4; k < AOMMIN(4, p_row + p_height - i - 4); ++k) { int sy = sy4 + delta * (k + 4); for (int l = -4; l < AOMMIN(4, p_col + p_width - j - 4); ++l) { const int offs = ROUND_POWER_OF_TWO(sy, WARPEDDIFF_PREC_BITS) + WARPEDPIXEL_PREC_SHIFTS; assert(offs >= 0 && offs <= WARPEDPIXEL_PREC_SHIFTS * 3); const int16_t *coeffs = av1_warped_filter[offs]; int32_t sum = 1 << offset_bits_vert; for (int m = 0; m < 8; ++m) { sum += tmp[(k + m + 4) * 8 + (l + 4)] * coeffs[m]; } if (conv_params->is_compound) { CONV_BUF_TYPE *p = &conv_params ->dst[(i - p_row + k + 4) * conv_params->dst_stride + (j - p_col + l + 4)]; sum = ROUND_POWER_OF_TWO(sum, reduce_bits_vert); if (conv_params->do_average) { uint16_t *dst16 = &pred[(i - p_row + k + 4) * p_stride + (j - p_col + l + 4)]; int32_t tmp32 = *p; if (conv_params->use_dist_wtd_comp_avg) { tmp32 = tmp32 * conv_params->fwd_offset + sum * conv_params->bck_offset; tmp32 = tmp32 >> DIST_PRECISION_BITS; } else { tmp32 += sum; tmp32 = tmp32 >> 1; } tmp32 = tmp32 - (1 << (offset_bits - conv_params->round_1)) - (1 << (offset_bits - conv_params->round_1 - 1)); *dst16 = clip_pixel_highbd(ROUND_POWER_OF_TWO(tmp32, round_bits), bd); } else { *p = sum; } } else { uint16_t *p = &pred[(i - p_row + k + 4) * p_stride + (j - p_col + l + 4)]; sum = ROUND_POWER_OF_TWO(sum, reduce_bits_vert); assert(0 <= sum && sum < (1 << (bd + 2))); *p = clip_pixel_highbd(sum - (1 << (bd - 1)) - (1 << bd), bd); } sy += gamma; } } } } } void highbd_warp_plane(WarpedMotionParams *wm, const uint16_t *const ref, int width, int height, int stride, uint16_t *const pred, int p_col, int p_row, int p_width, int p_height, int p_stride, int subsampling_x, int subsampling_y, int bd, ConvolveParams *conv_params) { const int32_t *const mat = wm->wmmat; const int16_t alpha = wm->alpha; const int16_t beta = wm->beta; const int16_t gamma = wm->gamma; const int16_t delta = wm->delta; av1_highbd_warp_affine(mat, ref, width, height, stride, pred, p_col, p_row, p_width, p_height, p_stride, subsampling_x, subsampling_y, bd, conv_params, alpha, beta, gamma, delta); } #endif // CONFIG_AV1_HIGHBITDEPTH /* The warp filter for ROTZOOM and AFFINE models works as follows: * Split the input into 8x8 blocks * For each block, project the point (4, 4) within the block, to get the overall block position. Split into integer and fractional coordinates, maintaining full WARPEDMODEL precision * Filter horizontally: Generate 15 rows of 8 pixels each. Each pixel gets a variable horizontal offset. This means that, while the rows of the intermediate buffer align with the rows of the *reference* image, the columns align with the columns of the *destination* image. * Filter vertically: Generate the output block (up to 8x8 pixels, but if the destination is too small we crop the output at this stage). Each pixel has a variable vertical offset, so that the resulting rows are aligned with the rows of the destination image. To accomplish these alignments, we factor the warp matrix as a product of two shear / asymmetric zoom matrices: / a b \ = / 1 0 \ * / 1+alpha beta \ \ c d / \ gamma 1+delta / \ 0 1 / where a, b, c, d are wmmat[2], wmmat[3], wmmat[4], wmmat[5] respectively. The horizontal shear (with alpha and beta) is applied first, then the vertical shear (with gamma and delta) is applied second. The only limitation is that, to fit this in a fixed 8-tap filter size, the fractional pixel offsets must be at most +-1. Since the horizontal filter generates 15 rows of 8 columns, and the initial point we project is at (4, 4) within the block, the parameters must satisfy 4 * |alpha| + 7 * |beta| <= 1 and 4 * |gamma| + 4 * |delta| <= 1 for this filter to be applicable. Note: This function assumes that the caller has done all of the relevant checks, ie. that we have a ROTZOOM or AFFINE model, that wm[4] and wm[5] are set appropriately (if using a ROTZOOM model), and that alpha, beta, gamma, delta are all in range. TODO(rachelbarker): Maybe support scaled references? */ /* A note on hardware implementation: The warp filter is intended to be implementable using the same hardware as the high-precision convolve filters from the loop-restoration and convolve-round experiments. For a single filter stage, considering all of the coefficient sets for the warp filter and the regular convolution filter, an input in the range [0, 2^k - 1] is mapped into the range [-56 * (2^k - 1), 184 * (2^k - 1)] before rounding. Allowing for some changes to the filter coefficient sets, call the range [-64 * 2^k, 192 * 2^k]. Then, if we initialize the accumulator to 64 * 2^k, we can replace this by the range [0, 256 * 2^k], which can be stored in an unsigned value with 8 + k bits. This allows the derivation of the appropriate bit widths and offsets for the various intermediate values: If F := FILTER_BITS = 7 (or else the above ranges need adjusting) So a *single* filter stage maps a k-bit input to a (k + F + 1)-bit intermediate value. H := ROUND0_BITS V := VERSHEAR_REDUCE_PREC_BITS (and note that we must have H + V = 2*F for the output to have the same scale as the input) then we end up with the following offsets and ranges: Horizontal filter: Apply an offset of 1 << (bd + F - 1), sum fits into a uint{bd + F + 1} After rounding: The values stored in 'tmp' fit into a uint{bd + F + 1 - H}. Vertical filter: Apply an offset of 1 << (bd + 2*F - H), sum fits into a uint{bd + 2*F + 2 - H} After rounding: The final value, before undoing the offset, fits into a uint{bd + 2}. Then we need to undo the offsets before clamping to a pixel. Note that, if we do this at the end, the amount to subtract is actually independent of H and V: offset to subtract = (1 << ((bd + F - 1) - H + F - V)) + (1 << ((bd + 2*F - H) - V)) == (1 << (bd - 1)) + (1 << bd) This allows us to entirely avoid clamping in both the warp filter and the convolve-round experiment. As of the time of writing, the Wiener filter from loop-restoration can encode a central coefficient up to 216, which leads to a maximum value of about 282 * 2^k after applying the offset. So in that case we still need to clamp. */ void av1_warp_affine_c(const int32_t *mat, const uint8_t *ref, int width, int height, int stride, uint8_t *pred, int p_col, int p_row, int p_width, int p_height, int p_stride, int subsampling_x, int subsampling_y, ConvolveParams *conv_params, int16_t alpha, int16_t beta, int16_t gamma, int16_t delta) { int32_t tmp[15 * 8]; const int bd = 8; const int reduce_bits_horiz = conv_params->round_0; const int reduce_bits_vert = conv_params->is_compound ? conv_params->round_1 : 2 * FILTER_BITS - reduce_bits_horiz; const int max_bits_horiz = bd + FILTER_BITS + 1 - reduce_bits_horiz; const int offset_bits_horiz = bd + FILTER_BITS - 1; const int offset_bits_vert = bd + 2 * FILTER_BITS - reduce_bits_horiz; const int round_bits = 2 * FILTER_BITS - conv_params->round_0 - conv_params->round_1; const int offset_bits = bd + 2 * FILTER_BITS - conv_params->round_0; (void)max_bits_horiz; assert(IMPLIES(conv_params->is_compound, conv_params->dst != NULL)); assert(IMPLIES(conv_params->do_average, conv_params->is_compound)); for (int i = p_row; i < p_row + p_height; i += 8) { for (int j = p_col; j < p_col + p_width; j += 8) { // Calculate the center of this 8x8 block, // project to luma coordinates (if in a subsampled chroma plane), // apply the affine transformation, // then convert back to the original coordinates (if necessary) const int32_t src_x = (j + 4) << subsampling_x; const int32_t src_y = (i + 4) << subsampling_y; const int64_t dst_x = (int64_t)mat[2] * src_x + (int64_t)mat[3] * src_y + (int64_t)mat[0]; const int64_t dst_y = (int64_t)mat[4] * src_x + (int64_t)mat[5] * src_y + (int64_t)mat[1]; const int64_t x4 = dst_x >> subsampling_x; const int64_t y4 = dst_y >> subsampling_y; int32_t ix4 = (int32_t)(x4 >> WARPEDMODEL_PREC_BITS); int32_t sx4 = x4 & ((1 << WARPEDMODEL_PREC_BITS) - 1); int32_t iy4 = (int32_t)(y4 >> WARPEDMODEL_PREC_BITS); int32_t sy4 = y4 & ((1 << WARPEDMODEL_PREC_BITS) - 1); sx4 += alpha * (-4) + beta * (-4); sy4 += gamma * (-4) + delta * (-4); sx4 &= ~((1 << WARP_PARAM_REDUCE_BITS) - 1); sy4 &= ~((1 << WARP_PARAM_REDUCE_BITS) - 1); // Horizontal filter for (int k = -7; k < 8; ++k) { // Clamp to top/bottom edge of the frame const int iy = clamp(iy4 + k, 0, height - 1); int sx = sx4 + beta * (k + 4); for (int l = -4; l < 4; ++l) { int ix = ix4 + l - 3; // At this point, sx = sx4 + alpha * l + beta * k const int offs = ROUND_POWER_OF_TWO(sx, WARPEDDIFF_PREC_BITS) + WARPEDPIXEL_PREC_SHIFTS; assert(offs >= 0 && offs <= WARPEDPIXEL_PREC_SHIFTS * 3); const int16_t *coeffs = av1_warped_filter[offs]; int32_t sum = 1 << offset_bits_horiz; for (int m = 0; m < 8; ++m) { // Clamp to left/right edge of the frame const int sample_x = clamp(ix + m, 0, width - 1); sum += ref[iy * stride + sample_x] * coeffs[m]; } sum = ROUND_POWER_OF_TWO(sum, reduce_bits_horiz); assert(0 <= sum && sum < (1 << max_bits_horiz)); tmp[(k + 7) * 8 + (l + 4)] = sum; sx += alpha; } } // Vertical filter for (int k = -4; k < AOMMIN(4, p_row + p_height - i - 4); ++k) { int sy = sy4 + delta * (k + 4); for (int l = -4; l < AOMMIN(4, p_col + p_width - j - 4); ++l) { // At this point, sy = sy4 + gamma * l + delta * k const int offs = ROUND_POWER_OF_TWO(sy, WARPEDDIFF_PREC_BITS) + WARPEDPIXEL_PREC_SHIFTS; assert(offs >= 0 && offs <= WARPEDPIXEL_PREC_SHIFTS * 3); const int16_t *coeffs = av1_warped_filter[offs]; int32_t sum = 1 << offset_bits_vert; for (int m = 0; m < 8; ++m) { sum += tmp[(k + m + 4) * 8 + (l + 4)] * coeffs[m]; } if (conv_params->is_compound) { CONV_BUF_TYPE *p = &conv_params ->dst[(i - p_row + k + 4) * conv_params->dst_stride + (j - p_col + l + 4)]; sum = ROUND_POWER_OF_TWO(sum, reduce_bits_vert); if (conv_params->do_average) { uint8_t *dst8 = &pred[(i - p_row + k + 4) * p_stride + (j - p_col + l + 4)]; int32_t tmp32 = *p; if (conv_params->use_dist_wtd_comp_avg) { tmp32 = tmp32 * conv_params->fwd_offset + sum * conv_params->bck_offset; tmp32 = tmp32 >> DIST_PRECISION_BITS; } else { tmp32 += sum; tmp32 = tmp32 >> 1; } tmp32 = tmp32 - (1 << (offset_bits - conv_params->round_1)) - (1 << (offset_bits - conv_params->round_1 - 1)); *dst8 = clip_pixel(ROUND_POWER_OF_TWO(tmp32, round_bits)); } else { *p = sum; } } else { uint8_t *p = &pred[(i - p_row + k + 4) * p_stride + (j - p_col + l + 4)]; sum = ROUND_POWER_OF_TWO(sum, reduce_bits_vert); assert(0 <= sum && sum < (1 << (bd + 2))); *p = clip_pixel(sum - (1 << (bd - 1)) - (1 << bd)); } sy += gamma; } } } } } void warp_plane(WarpedMotionParams *wm, const uint8_t *const ref, int width, int height, int stride, uint8_t *pred, int p_col, int p_row, int p_width, int p_height, int p_stride, int subsampling_x, int subsampling_y, ConvolveParams *conv_params) { const int32_t *const mat = wm->wmmat; const int16_t alpha = wm->alpha; const int16_t beta = wm->beta; const int16_t gamma = wm->gamma; const int16_t delta = wm->delta; av1_warp_affine(mat, ref, width, height, stride, pred, p_col, p_row, p_width, p_height, p_stride, subsampling_x, subsampling_y, conv_params, alpha, beta, gamma, delta); } void av1_warp_plane(WarpedMotionParams *wm, int use_hbd, int bd, const uint8_t *ref, int width, int height, int stride, uint8_t *pred, int p_col, int p_row, int p_width, int p_height, int p_stride, int subsampling_x, int subsampling_y, ConvolveParams *conv_params) { #if CONFIG_AV1_HIGHBITDEPTH if (use_hbd) highbd_warp_plane(wm, CONVERT_TO_SHORTPTR(ref), width, height, stride, CONVERT_TO_SHORTPTR(pred), p_col, p_row, p_width, p_height, p_stride, subsampling_x, subsampling_y, bd, conv_params); else warp_plane(wm, ref, width, height, stride, pred, p_col, p_row, p_width, p_height, p_stride, subsampling_x, subsampling_y, conv_params); #else (void)use_hbd; (void)bd; warp_plane(wm, ref, width, height, stride, pred, p_col, p_row, p_width, p_height, p_stride, subsampling_x, subsampling_y, conv_params); #endif } #define LS_MV_MAX 256 // max mv in 1/8-pel // Use LS_STEP = 8 so that 2 less bits needed for A, Bx, By. #define LS_STEP 8 // Assuming LS_MV_MAX is < MAX_SB_SIZE * 8, // the precision needed is: // (MAX_SB_SIZE_LOG2 + 3) [for sx * sx magnitude] + // (MAX_SB_SIZE_LOG2 + 4) [for sx * dx magnitude] + // 1 [for sign] + // LEAST_SQUARES_SAMPLES_MAX_BITS // [for adding up to LEAST_SQUARES_SAMPLES_MAX samples] // The value is 23 #define LS_MAT_RANGE_BITS \ ((MAX_SB_SIZE_LOG2 + 4) * 2 + LEAST_SQUARES_SAMPLES_MAX_BITS) // Bit-depth reduction from the full-range #define LS_MAT_DOWN_BITS 2 // bits range of A, Bx and By after downshifting #define LS_MAT_BITS (LS_MAT_RANGE_BITS - LS_MAT_DOWN_BITS) #define LS_MAT_MIN (-(1 << (LS_MAT_BITS - 1))) #define LS_MAT_MAX ((1 << (LS_MAT_BITS - 1)) - 1) // By setting LS_STEP = 8, the least 2 bits of every elements in A, Bx, By are // 0. So, we can reduce LS_MAT_RANGE_BITS(2) bits here. #define LS_SQUARE(a) \ (((a) * (a)*4 + (a)*4 * LS_STEP + LS_STEP * LS_STEP * 2) >> \ (2 + LS_MAT_DOWN_BITS)) #define LS_PRODUCT1(a, b) \ (((a) * (b)*4 + ((a) + (b)) * 2 * LS_STEP + LS_STEP * LS_STEP) >> \ (2 + LS_MAT_DOWN_BITS)) #define LS_PRODUCT2(a, b) \ (((a) * (b)*4 + ((a) + (b)) * 2 * LS_STEP + LS_STEP * LS_STEP * 2) >> \ (2 + LS_MAT_DOWN_BITS)) #define USE_LIMITED_PREC_MULT 0 #if USE_LIMITED_PREC_MULT #define MUL_PREC_BITS 16 static uint16_t resolve_multiplier_64(uint64_t D, int16_t *shift) { int msb = 0; uint16_t mult = 0; *shift = 0; if (D != 0) { msb = (int16_t)((D >> 32) ? get_msb((unsigned int)(D >> 32)) + 32 : get_msb((unsigned int)D)); if (msb >= MUL_PREC_BITS) { mult = (uint16_t)ROUND_POWER_OF_TWO_64(D, msb + 1 - MUL_PREC_BITS); *shift = msb + 1 - MUL_PREC_BITS; } else { mult = (uint16_t)D; *shift = 0; } } return mult; } static int32_t get_mult_shift_ndiag(int64_t Px, int16_t iDet, int shift) { int32_t ret; int16_t mshift; uint16_t Mul = resolve_multiplier_64(llabs(Px), &mshift); int32_t v = (int32_t)Mul * (int32_t)iDet * (Px < 0 ? -1 : 1); shift -= mshift; if (shift > 0) { return (int32_t)clamp(ROUND_POWER_OF_TWO_SIGNED(v, shift), -WARPEDMODEL_NONDIAGAFFINE_CLAMP + 1, WARPEDMODEL_NONDIAGAFFINE_CLAMP - 1); } else { return (int32_t)clamp(v * (1 << (-shift)), -WARPEDMODEL_NONDIAGAFFINE_CLAMP + 1, WARPEDMODEL_NONDIAGAFFINE_CLAMP - 1); } return ret; } static int32_t get_mult_shift_diag(int64_t Px, int16_t iDet, int shift) { int16_t mshift; uint16_t Mul = resolve_multiplier_64(llabs(Px), &mshift); int32_t v = (int32_t)Mul * (int32_t)iDet * (Px < 0 ? -1 : 1); shift -= mshift; if (shift > 0) { return (int32_t)clamp( ROUND_POWER_OF_TWO_SIGNED(v, shift), (1 << WARPEDMODEL_PREC_BITS) - WARPEDMODEL_NONDIAGAFFINE_CLAMP + 1, (1 << WARPEDMODEL_PREC_BITS) + WARPEDMODEL_NONDIAGAFFINE_CLAMP - 1); } else { return (int32_t)clamp( v * (1 << (-shift)), (1 << WARPEDMODEL_PREC_BITS) - WARPEDMODEL_NONDIAGAFFINE_CLAMP + 1, (1 << WARPEDMODEL_PREC_BITS) + WARPEDMODEL_NONDIAGAFFINE_CLAMP - 1); } } #else static int32_t get_mult_shift_ndiag(int64_t Px, int16_t iDet, int shift) { int64_t v = Px * (int64_t)iDet; return (int32_t)clamp64(ROUND_POWER_OF_TWO_SIGNED_64(v, shift), -WARPEDMODEL_NONDIAGAFFINE_CLAMP + 1, WARPEDMODEL_NONDIAGAFFINE_CLAMP - 1); } static int32_t get_mult_shift_diag(int64_t Px, int16_t iDet, int shift) { int64_t v = Px * (int64_t)iDet; return (int32_t)clamp64( ROUND_POWER_OF_TWO_SIGNED_64(v, shift), (1 << WARPEDMODEL_PREC_BITS) - WARPEDMODEL_NONDIAGAFFINE_CLAMP + 1, (1 << WARPEDMODEL_PREC_BITS) + WARPEDMODEL_NONDIAGAFFINE_CLAMP - 1); } #endif // USE_LIMITED_PREC_MULT static int find_affine_int(int np, const int *pts1, const int *pts2, BLOCK_SIZE bsize, int mvy, int mvx, WarpedMotionParams *wm, int mi_row, int mi_col) { int32_t A[2][2] = { { 0, 0 }, { 0, 0 } }; int32_t Bx[2] = { 0, 0 }; int32_t By[2] = { 0, 0 }; const int bw = block_size_wide[bsize]; const int bh = block_size_high[bsize]; const int rsuy = bh / 2 - 1; const int rsux = bw / 2 - 1; const int suy = rsuy * 8; const int sux = rsux * 8; const int duy = suy + mvy; const int dux = sux + mvx; // Assume the center pixel of the block has exactly the same motion vector // as transmitted for the block. First shift the origin of the source // points to the block center, and the origin of the destination points to // the block center added to the motion vector transmitted. // Let (xi, yi) denote the source points and (xi', yi') denote destination // points after origin shfifting, for i = 0, 1, 2, .... n-1. // Then if P = [x0, y0, // x1, y1 // x2, y1, // .... // ] // q = [x0', x1', x2', ... ]' // r = [y0', y1', y2', ... ]' // the least squares problems that need to be solved are: // [h1, h2]' = inv(P'P)P'q and // [h3, h4]' = inv(P'P)P'r // where the affine transformation is given by: // x' = h1.x + h2.y // y' = h3.x + h4.y // // The loop below computes: A = P'P, Bx = P'q, By = P'r // We need to just compute inv(A).Bx and inv(A).By for the solutions. // Contribution from neighbor block for (int i = 0; i < np; i++) { const int dx = pts2[i * 2] - dux; const int dy = pts2[i * 2 + 1] - duy; const int sx = pts1[i * 2] - sux; const int sy = pts1[i * 2 + 1] - suy; // (TODO)yunqing: This comparison wouldn't be necessary if the sample // selection is done in find_samples(). Also, global offset can be removed // while collecting samples. if (abs(sx - dx) < LS_MV_MAX && abs(sy - dy) < LS_MV_MAX) { A[0][0] += LS_SQUARE(sx); A[0][1] += LS_PRODUCT1(sx, sy); A[1][1] += LS_SQUARE(sy); Bx[0] += LS_PRODUCT2(sx, dx); Bx[1] += LS_PRODUCT1(sy, dx); By[0] += LS_PRODUCT1(sx, dy); By[1] += LS_PRODUCT2(sy, dy); } } // Just for debugging, and can be removed later. assert(A[0][0] >= LS_MAT_MIN && A[0][0] <= LS_MAT_MAX); assert(A[0][1] >= LS_MAT_MIN && A[0][1] <= LS_MAT_MAX); assert(A[1][1] >= LS_MAT_MIN && A[1][1] <= LS_MAT_MAX); assert(Bx[0] >= LS_MAT_MIN && Bx[0] <= LS_MAT_MAX); assert(Bx[1] >= LS_MAT_MIN && Bx[1] <= LS_MAT_MAX); assert(By[0] >= LS_MAT_MIN && By[0] <= LS_MAT_MAX); assert(By[1] >= LS_MAT_MIN && By[1] <= LS_MAT_MAX); // Compute Determinant of A const int64_t Det = (int64_t)A[0][0] * A[1][1] - (int64_t)A[0][1] * A[0][1]; if (Det == 0) return 1; int16_t shift; int16_t iDet = resolve_divisor_64(llabs(Det), &shift) * (Det < 0 ? -1 : 1); shift -= WARPEDMODEL_PREC_BITS; if (shift < 0) { iDet <<= (-shift); shift = 0; } int64_t Px[2], Py[2]; // These divided by the Det, are the least squares solutions Px[0] = (int64_t)A[1][1] * Bx[0] - (int64_t)A[0][1] * Bx[1]; Px[1] = -(int64_t)A[0][1] * Bx[0] + (int64_t)A[0][0] * Bx[1]; Py[0] = (int64_t)A[1][1] * By[0] - (int64_t)A[0][1] * By[1]; Py[1] = -(int64_t)A[0][1] * By[0] + (int64_t)A[0][0] * By[1]; wm->wmmat[2] = get_mult_shift_diag(Px[0], iDet, shift); wm->wmmat[3] = get_mult_shift_ndiag(Px[1], iDet, shift); wm->wmmat[4] = get_mult_shift_ndiag(Py[0], iDet, shift); wm->wmmat[5] = get_mult_shift_diag(Py[1], iDet, shift); const int isuy = (mi_row * MI_SIZE + rsuy); const int isux = (mi_col * MI_SIZE + rsux); // Note: In the vx, vy expressions below, the max value of each of the // 2nd and 3rd terms are (2^16 - 1) * (2^13 - 1). That leaves enough room // for the first term so that the overall sum in the worst case fits // within 32 bits overall. const int32_t vx = mvx * (1 << (WARPEDMODEL_PREC_BITS - 3)) - (isux * (wm->wmmat[2] - (1 << WARPEDMODEL_PREC_BITS)) + isuy * wm->wmmat[3]); const int32_t vy = mvy * (1 << (WARPEDMODEL_PREC_BITS - 3)) - (isux * wm->wmmat[4] + isuy * (wm->wmmat[5] - (1 << WARPEDMODEL_PREC_BITS))); wm->wmmat[0] = clamp(vx, -WARPEDMODEL_TRANS_CLAMP, WARPEDMODEL_TRANS_CLAMP - 1); wm->wmmat[1] = clamp(vy, -WARPEDMODEL_TRANS_CLAMP, WARPEDMODEL_TRANS_CLAMP - 1); return 0; } int av1_find_projection(int np, const int *pts1, const int *pts2, BLOCK_SIZE bsize, int mvy, int mvx, WarpedMotionParams *wm_params, int mi_row, int mi_col) { assert(wm_params->wmtype == AFFINE); if (find_affine_int(np, pts1, pts2, bsize, mvy, mvx, wm_params, mi_row, mi_col)) return 1; // check compatibility with the fast warp filter if (!av1_get_shear_params(wm_params)) return 1; return 0; }