+static int decode_speedhq_border(const SHQContext *s, GetBitContext *gb, AVFrame *frame, int field_number, int line_stride)
+{
+ int linesize_y = frame->linesize[0] * line_stride;
+ int linesize_cb = frame->linesize[1] * line_stride;
+ int linesize_cr = frame->linesize[2] * line_stride;
+ int linesize_a;
+ int ret;
+
+ if (s->alpha_type != SHQ_NO_ALPHA)
+ linesize_a = frame->linesize[3] * line_stride;
+
+ for (int y = 0; y < frame->height; y += 16 * line_stride) {
+ int last_dc[4] = { 1024, 1024, 1024, 1024 };
+ uint8_t *dest_y, *dest_cb, *dest_cr, *dest_a;
+ uint8_t last_alpha[16];
+ int x = frame->width - 8;
+
+ dest_y = frame->data[0] + frame->linesize[0] * (y + field_number) + x;
+ if (s->subsampling == SHQ_SUBSAMPLING_420) {
+ dest_cb = frame->data[1] + frame->linesize[1] * (y/2 + field_number) + x / 2;
+ dest_cr = frame->data[2] + frame->linesize[2] * (y/2 + field_number) + x / 2;
+ } else if (s->subsampling == SHQ_SUBSAMPLING_422) {
+ dest_cb = frame->data[1] + frame->linesize[1] * (y + field_number) + x / 2;
+ dest_cr = frame->data[2] + frame->linesize[2] * (y + field_number) + x / 2;
+ }
+ if (s->alpha_type != SHQ_NO_ALPHA) {
+ memset(last_alpha, 255, sizeof(last_alpha));
+ dest_a = frame->data[3] + frame->linesize[3] * (y + field_number) + x;
+ }
+
+ if ((ret = decode_dct_block(s, gb, last_dc, 0, dest_y, linesize_y)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 0, dest_y + 8, linesize_y)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 0, dest_y + 8 * linesize_y, linesize_y)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 0, dest_y + 8 * linesize_y + 8, linesize_y)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 1, dest_cb, linesize_cb)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 2, dest_cr, linesize_cr)) < 0)
+ return ret;
+
+ if (s->subsampling != SHQ_SUBSAMPLING_420) {
+ if ((ret = decode_dct_block(s, gb, last_dc, 1, dest_cb + 8 * linesize_cb, linesize_cb)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 2, dest_cr + 8 * linesize_cr, linesize_cr)) < 0)
+ return ret;
+ }
+
+ if (s->alpha_type == SHQ_RLE_ALPHA) {
+ /* Alpha coded using 16x8 RLE blocks. */
+ if ((ret = decode_alpha_block(s, gb, last_alpha, dest_a, linesize_a)) < 0)
+ return ret;
+ if ((ret = decode_alpha_block(s, gb, last_alpha, dest_a + 8 * linesize_a, linesize_a)) < 0)
+ return ret;
+ } else if (s->alpha_type == SHQ_DCT_ALPHA) {
+ /* Alpha encoded exactly like luma. */
+ if ((ret = decode_dct_block(s, gb, last_dc, 3, dest_a, linesize_a)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 3, dest_a + 8, linesize_a)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 3, dest_a + 8 * linesize_a, linesize_a)) < 0)
+ return ret;
+ if ((ret = decode_dct_block(s, gb, last_dc, 3, dest_a + 8 * linesize_a + 8, linesize_a)) < 0)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+