static int jpg_decode_data(JPGContext *c, int width, int height, const uint8_t *src, int src_size, uint8_t *dst, int dst_stride, const uint8_t *mask, int mask_stride, int num_mbs, int swapuv) { GetBitContext gb; int mb_w, mb_h, mb_x, mb_y, i, j; int bx, by; int unesc_size; int ret; if ((ret = av_reallocp(&c->buf, src_size + FF_INPUT_BUFFER_PADDING_SIZE)) < 0) return ret; jpg_unescape(src, src_size, c->buf, &unesc_size); memset(c->buf + unesc_size, 0, FF_INPUT_BUFFER_PADDING_SIZE); init_get_bits8(&gb, c->buf, unesc_size); width = FFALIGN(width, 16); mb_w = width >> 4; mb_h = (height + 15) >> 4; if (!num_mbs) num_mbs = mb_w * mb_h * 4; for (i = 0; i < 3; i++) c->prev_dc[i] = 1024; bx = by = 0; c->bdsp.clear_blocks(c->block[0]); for (mb_y = 0; mb_y < mb_h; mb_y++) { for (mb_x = 0; mb_x < mb_w; mb_x++) { if (mask && !mask[mb_x * 2] && !mask[mb_x * 2 + 1] && !mask[mb_x * 2 + mask_stride] && !mask[mb_x * 2 + 1 + mask_stride]) { bx += 16; continue; } for (j = 0; j < 2; j++) { for (i = 0; i < 2; i++) { if (mask && !mask[mb_x * 2 + i + j * mask_stride]) continue; num_mbs--; if ((ret = jpg_decode_block(c, &gb, 0, c->block[i + j * 2])) != 0) return ret; c->idsp.idct(c->block[i + j * 2]); } } for (i = 1; i < 3; i++) { if ((ret = jpg_decode_block(c, &gb, i, c->block[i + 3])) != 0) return ret; c->idsp.idct(c->block[i + 3]); } for (j = 0; j < 16; j++) { uint8_t *out = dst + bx * 3 + (by + j) * dst_stride; for (i = 0; i < 16; i++) { int Y, U, V; Y = c->block[(j >> 3) * 2 + (i >> 3)][(i & 7) + (j & 7) * 8]; U = c->block[4 ^ swapuv][(i >> 1) + (j >> 1) * 8] - 128; V = c->block[5 ^ swapuv][(i >> 1) + (j >> 1) * 8] - 128; yuv2rgb(out + i * 3, Y, U, V); } } if (!num_mbs) return 0; bx += 16; } bx = 0; by += 16; if (mask) mask += mask_stride * 2; } return 0; }