1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libvpx/vp9/common/vp9_pred_common.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,419 @@
1.4 +
1.5 +/*
1.6 + * Copyright (c) 2012 The WebM project authors. All Rights Reserved.
1.7 + *
1.8 + * Use of this source code is governed by a BSD-style license
1.9 + * that can be found in the LICENSE file in the root of the source
1.10 + * tree. An additional intellectual property rights grant can be found
1.11 + * in the file PATENTS. All contributing project authors may
1.12 + * be found in the AUTHORS file in the root of the source tree.
1.13 + */
1.14 +
1.15 +#include <limits.h>
1.16 +
1.17 +#include "vp9/common/vp9_common.h"
1.18 +#include "vp9/common/vp9_pred_common.h"
1.19 +#include "vp9/common/vp9_seg_common.h"
1.20 +#include "vp9/common/vp9_treecoder.h"
1.21 +
1.22 +static INLINE const MB_MODE_INFO *get_above_mbmi(const MODE_INFO *const above) {
1.23 + return (above != NULL) ? &above->mbmi : NULL;
1.24 +}
1.25 +
1.26 +static INLINE const MB_MODE_INFO *get_left_mbmi(const MODE_INFO *const left) {
1.27 + return (left != NULL) ? &left->mbmi : NULL;
1.28 +}
1.29 +
1.30 +// Returns a context number for the given MB prediction signal
1.31 +unsigned char vp9_get_pred_context_switchable_interp(const MACROBLOCKD *xd) {
1.32 + const MODE_INFO *const above_mi = get_above_mi(xd);
1.33 + const MODE_INFO *const left_mi = get_left_mi(xd);
1.34 + const int above_in_image = above_mi != NULL;
1.35 + const int left_in_image = left_mi != NULL;
1.36 + // Note:
1.37 + // The mode info data structure has a one element border above and to the
1.38 + // left of the entries correpsonding to real macroblocks.
1.39 + // The prediction flags in these dummy entries are initialised to 0.
1.40 + // left
1.41 + const int left_mv_pred = left_in_image ? is_inter_block(&left_mi->mbmi)
1.42 + : 0;
1.43 + const int left_interp = left_in_image && left_mv_pred
1.44 + ? left_mi->mbmi.interp_filter
1.45 + : SWITCHABLE_FILTERS;
1.46 +
1.47 + // above
1.48 + const int above_mv_pred = above_in_image ? is_inter_block(&above_mi->mbmi)
1.49 + : 0;
1.50 + const int above_interp = above_in_image && above_mv_pred
1.51 + ? above_mi->mbmi.interp_filter
1.52 + : SWITCHABLE_FILTERS;
1.53 +
1.54 + if (left_interp == above_interp)
1.55 + return left_interp;
1.56 + else if (left_interp == SWITCHABLE_FILTERS &&
1.57 + above_interp != SWITCHABLE_FILTERS)
1.58 + return above_interp;
1.59 + else if (left_interp != SWITCHABLE_FILTERS &&
1.60 + above_interp == SWITCHABLE_FILTERS)
1.61 + return left_interp;
1.62 + else
1.63 + return SWITCHABLE_FILTERS;
1.64 +}
1.65 +// Returns a context number for the given MB prediction signal
1.66 +unsigned char vp9_get_pred_context_intra_inter(const MACROBLOCKD *xd) {
1.67 + const MODE_INFO *const above_mi = get_above_mi(xd);
1.68 + const MODE_INFO *const left_mi = get_left_mi(xd);
1.69 + const MB_MODE_INFO *const above_mbmi = get_above_mbmi(above_mi);
1.70 + const MB_MODE_INFO *const left_mbmi = get_left_mbmi(left_mi);
1.71 + const int above_in_image = above_mi != NULL;
1.72 + const int left_in_image = left_mi != NULL;
1.73 + const int above_intra = above_in_image ? !is_inter_block(above_mbmi) : 1;
1.74 + const int left_intra = left_in_image ? !is_inter_block(left_mbmi) : 1;
1.75 +
1.76 + // The mode info data structure has a one element border above and to the
1.77 + // left of the entries corresponding to real macroblocks.
1.78 + // The prediction flags in these dummy entries are initialized to 0.
1.79 + // 0 - inter/inter, inter/--, --/inter, --/--
1.80 + // 1 - intra/inter, inter/intra
1.81 + // 2 - intra/--, --/intra
1.82 + // 3 - intra/intra
1.83 + if (above_in_image && left_in_image) // both edges available
1.84 + return left_intra && above_intra ? 3
1.85 + : left_intra || above_intra;
1.86 + else if (above_in_image || left_in_image) // one edge available
1.87 + return 2 * (above_in_image ? above_intra : left_intra);
1.88 + else
1.89 + return 0;
1.90 +}
1.91 +// Returns a context number for the given MB prediction signal
1.92 +unsigned char vp9_get_pred_context_comp_inter_inter(const VP9_COMMON *cm,
1.93 + const MACROBLOCKD *xd) {
1.94 + int pred_context;
1.95 + const MODE_INFO *const above_mi = get_above_mi(xd);
1.96 + const MODE_INFO *const left_mi = get_left_mi(xd);
1.97 + const MB_MODE_INFO *const above_mbmi = get_above_mbmi(above_mi);
1.98 + const MB_MODE_INFO *const left_mbmi = get_left_mbmi(left_mi);
1.99 + const int above_in_image = above_mi != NULL;
1.100 + const int left_in_image = left_mi != NULL;
1.101 + // Note:
1.102 + // The mode info data structure has a one element border above and to the
1.103 + // left of the entries correpsonding to real macroblocks.
1.104 + // The prediction flags in these dummy entries are initialised to 0.
1.105 + if (above_in_image && left_in_image) { // both edges available
1.106 + if (!has_second_ref(above_mbmi) && !has_second_ref(left_mbmi))
1.107 + // neither edge uses comp pred (0/1)
1.108 + pred_context = (above_mbmi->ref_frame[0] == cm->comp_fixed_ref) ^
1.109 + (left_mbmi->ref_frame[0] == cm->comp_fixed_ref);
1.110 + else if (!has_second_ref(above_mbmi))
1.111 + // one of two edges uses comp pred (2/3)
1.112 + pred_context = 2 + (above_mbmi->ref_frame[0] == cm->comp_fixed_ref ||
1.113 + !is_inter_block(above_mbmi));
1.114 + else if (!has_second_ref(left_mbmi))
1.115 + // one of two edges uses comp pred (2/3)
1.116 + pred_context = 2 + (left_mbmi->ref_frame[0] == cm->comp_fixed_ref ||
1.117 + !is_inter_block(left_mbmi));
1.118 + else // both edges use comp pred (4)
1.119 + pred_context = 4;
1.120 + } else if (above_in_image || left_in_image) { // one edge available
1.121 + const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
1.122 +
1.123 + if (!has_second_ref(edge_mbmi))
1.124 + // edge does not use comp pred (0/1)
1.125 + pred_context = edge_mbmi->ref_frame[0] == cm->comp_fixed_ref;
1.126 + else
1.127 + // edge uses comp pred (3)
1.128 + pred_context = 3;
1.129 + } else { // no edges available (1)
1.130 + pred_context = 1;
1.131 + }
1.132 + assert(pred_context >= 0 && pred_context < COMP_INTER_CONTEXTS);
1.133 + return pred_context;
1.134 +}
1.135 +
1.136 +// Returns a context number for the given MB prediction signal
1.137 +unsigned char vp9_get_pred_context_comp_ref_p(const VP9_COMMON *cm,
1.138 + const MACROBLOCKD *xd) {
1.139 + int pred_context;
1.140 + const MODE_INFO *const above_mi = get_above_mi(xd);
1.141 + const MODE_INFO *const left_mi = get_left_mi(xd);
1.142 + const MB_MODE_INFO *const above_mbmi = get_above_mbmi(above_mi);
1.143 + const MB_MODE_INFO *const left_mbmi = get_left_mbmi(left_mi);
1.144 + const int above_in_image = above_mi != NULL;
1.145 + const int left_in_image = left_mi != NULL;
1.146 + const int above_intra = above_in_image ? !is_inter_block(above_mbmi) : 1;
1.147 + const int left_intra = left_in_image ? !is_inter_block(left_mbmi) : 1;
1.148 + // Note:
1.149 + // The mode info data structure has a one element border above and to the
1.150 + // left of the entries correpsonding to real macroblocks.
1.151 + // The prediction flags in these dummy entries are initialised to 0.
1.152 + const int fix_ref_idx = cm->ref_frame_sign_bias[cm->comp_fixed_ref];
1.153 + const int var_ref_idx = !fix_ref_idx;
1.154 +
1.155 + if (above_in_image && left_in_image) { // both edges available
1.156 + if (above_intra && left_intra) { // intra/intra (2)
1.157 + pred_context = 2;
1.158 + } else if (above_intra || left_intra) { // intra/inter
1.159 + const MB_MODE_INFO *edge_mbmi = above_intra ? left_mbmi : above_mbmi;
1.160 +
1.161 + if (!has_second_ref(edge_mbmi)) // single pred (1/3)
1.162 + pred_context = 1 + 2 * (edge_mbmi->ref_frame[0] != cm->comp_var_ref[1]);
1.163 + else // comp pred (1/3)
1.164 + pred_context = 1 + 2 * (edge_mbmi->ref_frame[var_ref_idx]
1.165 + != cm->comp_var_ref[1]);
1.166 + } else { // inter/inter
1.167 + const int l_sg = !has_second_ref(left_mbmi);
1.168 + const int a_sg = !has_second_ref(above_mbmi);
1.169 + MV_REFERENCE_FRAME vrfa = a_sg ? above_mbmi->ref_frame[0]
1.170 + : above_mbmi->ref_frame[var_ref_idx];
1.171 + MV_REFERENCE_FRAME vrfl = l_sg ? left_mbmi->ref_frame[0]
1.172 + : left_mbmi->ref_frame[var_ref_idx];
1.173 +
1.174 + if (vrfa == vrfl && cm->comp_var_ref[1] == vrfa) {
1.175 + pred_context = 0;
1.176 + } else if (l_sg && a_sg) { // single/single
1.177 + if ((vrfa == cm->comp_fixed_ref && vrfl == cm->comp_var_ref[0]) ||
1.178 + (vrfl == cm->comp_fixed_ref && vrfa == cm->comp_var_ref[0]))
1.179 + pred_context = 4;
1.180 + else if (vrfa == vrfl)
1.181 + pred_context = 3;
1.182 + else
1.183 + pred_context = 1;
1.184 + } else if (l_sg || a_sg) { // single/comp
1.185 + MV_REFERENCE_FRAME vrfc = l_sg ? vrfa : vrfl;
1.186 + MV_REFERENCE_FRAME rfs = a_sg ? vrfa : vrfl;
1.187 + if (vrfc == cm->comp_var_ref[1] && rfs != cm->comp_var_ref[1])
1.188 + pred_context = 1;
1.189 + else if (rfs == cm->comp_var_ref[1] && vrfc != cm->comp_var_ref[1])
1.190 + pred_context = 2;
1.191 + else
1.192 + pred_context = 4;
1.193 + } else if (vrfa == vrfl) { // comp/comp
1.194 + pred_context = 4;
1.195 + } else {
1.196 + pred_context = 2;
1.197 + }
1.198 + }
1.199 + } else if (above_in_image || left_in_image) { // one edge available
1.200 + const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
1.201 +
1.202 + if (!is_inter_block(edge_mbmi)) {
1.203 + pred_context = 2;
1.204 + } else {
1.205 + if (has_second_ref(edge_mbmi))
1.206 + pred_context = 4 * (edge_mbmi->ref_frame[var_ref_idx]
1.207 + != cm->comp_var_ref[1]);
1.208 + else
1.209 + pred_context = 3 * (edge_mbmi->ref_frame[0] != cm->comp_var_ref[1]);
1.210 + }
1.211 + } else { // no edges available (2)
1.212 + pred_context = 2;
1.213 + }
1.214 + assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
1.215 +
1.216 + return pred_context;
1.217 +}
1.218 +unsigned char vp9_get_pred_context_single_ref_p1(const MACROBLOCKD *xd) {
1.219 + int pred_context;
1.220 + const MODE_INFO *const above_mi = get_above_mi(xd);
1.221 + const MODE_INFO *const left_mi = get_left_mi(xd);
1.222 + const MB_MODE_INFO *const above_mbmi = get_above_mbmi(above_mi);
1.223 + const MB_MODE_INFO *const left_mbmi = get_left_mbmi(left_mi);
1.224 + const int above_in_image = above_mi != NULL;
1.225 + const int left_in_image = left_mi != NULL;
1.226 + const int above_intra = above_in_image ? !is_inter_block(above_mbmi) : 1;
1.227 + const int left_intra = left_in_image ? !is_inter_block(left_mbmi) : 1;
1.228 + // Note:
1.229 + // The mode info data structure has a one element border above and to the
1.230 + // left of the entries correpsonding to real macroblocks.
1.231 + // The prediction flags in these dummy entries are initialised to 0.
1.232 + if (above_in_image && left_in_image) { // both edges available
1.233 + if (above_intra && left_intra) { // intra/intra
1.234 + pred_context = 2;
1.235 + } else if (above_intra || left_intra) { // intra/inter or inter/intra
1.236 + const MB_MODE_INFO *edge_mbmi = above_intra ? left_mbmi : above_mbmi;
1.237 + if (!has_second_ref(edge_mbmi))
1.238 + pred_context = 4 * (edge_mbmi->ref_frame[0] == LAST_FRAME);
1.239 + else
1.240 + pred_context = 1 + (edge_mbmi->ref_frame[0] == LAST_FRAME ||
1.241 + edge_mbmi->ref_frame[1] == LAST_FRAME);
1.242 + } else { // inter/inter
1.243 + if (!has_second_ref(above_mbmi) && !has_second_ref(left_mbmi)) {
1.244 + pred_context = 2 * (above_mbmi->ref_frame[0] == LAST_FRAME) +
1.245 + 2 * (left_mbmi->ref_frame[0] == LAST_FRAME);
1.246 + } else if (has_second_ref(above_mbmi) && has_second_ref(left_mbmi)) {
1.247 + pred_context = 1 + (above_mbmi->ref_frame[0] == LAST_FRAME ||
1.248 + above_mbmi->ref_frame[1] == LAST_FRAME ||
1.249 + left_mbmi->ref_frame[0] == LAST_FRAME ||
1.250 + left_mbmi->ref_frame[1] == LAST_FRAME);
1.251 + } else {
1.252 + const MV_REFERENCE_FRAME rfs = !has_second_ref(above_mbmi) ?
1.253 + above_mbmi->ref_frame[0] : left_mbmi->ref_frame[0];
1.254 + const MV_REFERENCE_FRAME crf1 = has_second_ref(above_mbmi) ?
1.255 + above_mbmi->ref_frame[0] : left_mbmi->ref_frame[0];
1.256 + const MV_REFERENCE_FRAME crf2 = has_second_ref(above_mbmi) ?
1.257 + above_mbmi->ref_frame[1] : left_mbmi->ref_frame[1];
1.258 +
1.259 + if (rfs == LAST_FRAME)
1.260 + pred_context = 3 + (crf1 == LAST_FRAME || crf2 == LAST_FRAME);
1.261 + else
1.262 + pred_context = crf1 == LAST_FRAME || crf2 == LAST_FRAME;
1.263 + }
1.264 + }
1.265 + } else if (above_in_image || left_in_image) { // one edge available
1.266 + const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
1.267 + if (!is_inter_block(edge_mbmi)) { // intra
1.268 + pred_context = 2;
1.269 + } else { // inter
1.270 + if (!has_second_ref(edge_mbmi))
1.271 + pred_context = 4 * (edge_mbmi->ref_frame[0] == LAST_FRAME);
1.272 + else
1.273 + pred_context = 1 + (edge_mbmi->ref_frame[0] == LAST_FRAME ||
1.274 + edge_mbmi->ref_frame[1] == LAST_FRAME);
1.275 + }
1.276 + } else { // no edges available
1.277 + pred_context = 2;
1.278 + }
1.279 +
1.280 + assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
1.281 + return pred_context;
1.282 +}
1.283 +
1.284 +unsigned char vp9_get_pred_context_single_ref_p2(const MACROBLOCKD *xd) {
1.285 + int pred_context;
1.286 + const MODE_INFO *const above_mi = get_above_mi(xd);
1.287 + const MODE_INFO *const left_mi = get_left_mi(xd);
1.288 + const MB_MODE_INFO *const above_mbmi = get_above_mbmi(above_mi);
1.289 + const MB_MODE_INFO *const left_mbmi = get_left_mbmi(left_mi);
1.290 + const int above_in_image = above_mi != NULL;
1.291 + const int left_in_image = left_mi != NULL;
1.292 + const int above_intra = above_in_image ? !is_inter_block(above_mbmi) : 1;
1.293 + const int left_intra = left_in_image ? !is_inter_block(left_mbmi) : 1;
1.294 +
1.295 + // Note:
1.296 + // The mode info data structure has a one element border above and to the
1.297 + // left of the entries correpsonding to real macroblocks.
1.298 + // The prediction flags in these dummy entries are initialised to 0.
1.299 + if (above_in_image && left_in_image) { // both edges available
1.300 + if (above_intra && left_intra) { // intra/intra
1.301 + pred_context = 2;
1.302 + } else if (above_intra || left_intra) { // intra/inter or inter/intra
1.303 + const MB_MODE_INFO *edge_mbmi = above_intra ? left_mbmi : above_mbmi;
1.304 + if (!has_second_ref(edge_mbmi)) {
1.305 + if (edge_mbmi->ref_frame[0] == LAST_FRAME)
1.306 + pred_context = 3;
1.307 + else
1.308 + pred_context = 4 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME);
1.309 + } else {
1.310 + pred_context = 1 + 2 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME ||
1.311 + edge_mbmi->ref_frame[1] == GOLDEN_FRAME);
1.312 + }
1.313 + } else { // inter/inter
1.314 + if (!has_second_ref(above_mbmi) && !has_second_ref(left_mbmi)) {
1.315 + if (above_mbmi->ref_frame[0] == LAST_FRAME &&
1.316 + left_mbmi->ref_frame[0] == LAST_FRAME) {
1.317 + pred_context = 3;
1.318 + } else if (above_mbmi->ref_frame[0] == LAST_FRAME ||
1.319 + left_mbmi->ref_frame[0] == LAST_FRAME) {
1.320 + const MB_MODE_INFO *edge_mbmi =
1.321 + above_mbmi->ref_frame[0] == LAST_FRAME ? left_mbmi : above_mbmi;
1.322 +
1.323 + pred_context = 4 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME);
1.324 + } else {
1.325 + pred_context = 2 * (above_mbmi->ref_frame[0] == GOLDEN_FRAME) +
1.326 + 2 * (left_mbmi->ref_frame[0] == GOLDEN_FRAME);
1.327 + }
1.328 + } else if (has_second_ref(above_mbmi) && has_second_ref(left_mbmi)) {
1.329 + if (above_mbmi->ref_frame[0] == left_mbmi->ref_frame[0] &&
1.330 + above_mbmi->ref_frame[1] == left_mbmi->ref_frame[1])
1.331 + pred_context = 3 * (above_mbmi->ref_frame[0] == GOLDEN_FRAME ||
1.332 + above_mbmi->ref_frame[1] == GOLDEN_FRAME ||
1.333 + left_mbmi->ref_frame[0] == GOLDEN_FRAME ||
1.334 + left_mbmi->ref_frame[1] == GOLDEN_FRAME);
1.335 + else
1.336 + pred_context = 2;
1.337 + } else {
1.338 + const MV_REFERENCE_FRAME rfs = !has_second_ref(above_mbmi) ?
1.339 + above_mbmi->ref_frame[0] : left_mbmi->ref_frame[0];
1.340 + const MV_REFERENCE_FRAME crf1 = has_second_ref(above_mbmi) ?
1.341 + above_mbmi->ref_frame[0] : left_mbmi->ref_frame[0];
1.342 + const MV_REFERENCE_FRAME crf2 = has_second_ref(above_mbmi) ?
1.343 + above_mbmi->ref_frame[1] : left_mbmi->ref_frame[1];
1.344 +
1.345 + if (rfs == GOLDEN_FRAME)
1.346 + pred_context = 3 + (crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME);
1.347 + else if (rfs == ALTREF_FRAME)
1.348 + pred_context = crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME;
1.349 + else
1.350 + pred_context = 1 + 2 * (crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME);
1.351 + }
1.352 + }
1.353 + } else if (above_in_image || left_in_image) { // one edge available
1.354 + const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
1.355 +
1.356 + if (!is_inter_block(edge_mbmi) ||
1.357 + (edge_mbmi->ref_frame[0] == LAST_FRAME && !has_second_ref(edge_mbmi)))
1.358 + pred_context = 2;
1.359 + else if (!has_second_ref(edge_mbmi))
1.360 + pred_context = 4 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME);
1.361 + else
1.362 + pred_context = 3 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME ||
1.363 + edge_mbmi->ref_frame[1] == GOLDEN_FRAME);
1.364 + } else { // no edges available (2)
1.365 + pred_context = 2;
1.366 + }
1.367 + assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
1.368 + return pred_context;
1.369 +}
1.370 +// Returns a context number for the given MB prediction signal
1.371 +// The mode info data structure has a one element border above and to the
1.372 +// left of the entries corresponding to real blocks.
1.373 +// The prediction flags in these dummy entries are initialized to 0.
1.374 +unsigned char vp9_get_pred_context_tx_size(const MACROBLOCKD *xd) {
1.375 + const MODE_INFO *const above_mi = get_above_mi(xd);
1.376 + const MODE_INFO *const left_mi = get_left_mi(xd);
1.377 + const MB_MODE_INFO *const above_mbmi = get_above_mbmi(above_mi);
1.378 + const MB_MODE_INFO *const left_mbmi = get_left_mbmi(left_mi);
1.379 + const int above_in_image = above_mi != NULL;
1.380 + const int left_in_image = left_mi != NULL;
1.381 + const int max_tx_size = max_txsize_lookup[xd->mi_8x8[0]->mbmi.sb_type];
1.382 + int above_context = max_tx_size;
1.383 + int left_context = max_tx_size;
1.384 +
1.385 + if (above_in_image)
1.386 + above_context = above_mbmi->skip_coeff ? max_tx_size
1.387 + : above_mbmi->tx_size;
1.388 +
1.389 + if (left_in_image)
1.390 + left_context = left_mbmi->skip_coeff ? max_tx_size
1.391 + : left_mbmi->tx_size;
1.392 +
1.393 + if (!left_in_image)
1.394 + left_context = above_context;
1.395 +
1.396 + if (!above_in_image)
1.397 + above_context = left_context;
1.398 +
1.399 + return above_context + left_context > max_tx_size;
1.400 +}
1.401 +
1.402 +void vp9_set_pred_flag_seg_id(MACROBLOCKD *xd, uint8_t pred_flag) {
1.403 + xd->mi_8x8[0]->mbmi.seg_id_predicted = pred_flag;
1.404 +}
1.405 +
1.406 +int vp9_get_segment_id(VP9_COMMON *cm, const uint8_t *segment_ids,
1.407 + BLOCK_SIZE bsize, int mi_row, int mi_col) {
1.408 + const int mi_offset = mi_row * cm->mi_cols + mi_col;
1.409 + const int bw = num_8x8_blocks_wide_lookup[bsize];
1.410 + const int bh = num_8x8_blocks_high_lookup[bsize];
1.411 + const int xmis = MIN(cm->mi_cols - mi_col, bw);
1.412 + const int ymis = MIN(cm->mi_rows - mi_row, bh);
1.413 + int x, y, segment_id = INT_MAX;
1.414 +
1.415 + for (y = 0; y < ymis; y++)
1.416 + for (x = 0; x < xmis; x++)
1.417 + segment_id = MIN(segment_id,
1.418 + segment_ids[mi_offset + y * cm->mi_cols + x]);
1.419 +
1.420 + assert(segment_id >= 0 && segment_id < MAX_SEGMENTS);
1.421 + return segment_id;
1.422 +}
