1/* 2 * Copyright (c) 1990 James Ashton - Sydney University 3 * Copyright (c) 2012 Stefano Sabatini 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22/** 23 * @file 24 * X-Face encoder, based on libcompface, by James Ashton. 25 */ 26 27#include "xface.h" 28#include "avcodec.h" 29#include "internal.h" 30 31typedef struct XFaceContext { 32 AVClass *class; 33 uint8_t bitmap[XFACE_PIXELS]; ///< image used internally for decoding 34 int max_line_len; ///< max line length for compressed data 35 int set_header; ///< set X-Face header in the output 36} XFaceContext; 37 38static int all_same(char *bitmap, int w, int h) 39{ 40 char val, *row; 41 int x; 42 43 val = *bitmap; 44 while (h--) { 45 row = bitmap; 46 x = w; 47 while (x--) 48 if (*(row++) != val) 49 return 0; 50 bitmap += XFACE_WIDTH; 51 } 52 return 1; 53} 54 55static int all_black(char *bitmap, int w, int h) 56{ 57 if (w > 3) { 58 w /= 2; 59 h /= 2; 60 return (all_black(bitmap, w, h) && all_black(bitmap + w, w, h) && 61 all_black(bitmap + XFACE_WIDTH * h, w, h) && 62 all_black(bitmap + XFACE_WIDTH * h + w, w, h)); 63 } else { 64 /* at least one pixel in the 2x2 grid is non-zero */ 65 return *bitmap || *(bitmap + 1) || 66 *(bitmap + XFACE_WIDTH) || *(bitmap + XFACE_WIDTH + 1); 67 } 68} 69 70static int all_white(char *bitmap, int w, int h) 71{ 72 return *bitmap == 0 && all_same(bitmap, w, h); 73} 74 75typedef struct { 76 const ProbRange *prob_ranges[XFACE_PIXELS*2]; 77 int prob_ranges_idx; 78} ProbRangesQueue; 79 80static inline int pq_push(ProbRangesQueue *pq, const ProbRange *p) 81{ 82 if (pq->prob_ranges_idx >= XFACE_PIXELS * 2 - 1) 83 return -1; 84 pq->prob_ranges[pq->prob_ranges_idx++] = p; 85 return 0; 86} 87 88static void push_greys(ProbRangesQueue *pq, char *bitmap, int w, int h) 89{ 90 if (w > 3) { 91 w /= 2; 92 h /= 2; 93 push_greys(pq, bitmap, w, h); 94 push_greys(pq, bitmap + w, w, h); 95 push_greys(pq, bitmap + XFACE_WIDTH * h, w, h); 96 push_greys(pq, bitmap + XFACE_WIDTH * h + w, w, h); 97 } else { 98 const ProbRange *p = ff_xface_probranges_2x2 + 99 *bitmap + 100 2 * *(bitmap + 1) + 101 4 * *(bitmap + XFACE_WIDTH) + 102 8 * *(bitmap + XFACE_WIDTH + 1); 103 pq_push(pq, p); 104 } 105} 106 107static void encode_block(char *bitmap, int w, int h, int level, ProbRangesQueue *pq) 108{ 109 if (all_white(bitmap, w, h)) { 110 pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_WHITE]); 111 } else if (all_black(bitmap, w, h)) { 112 pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_BLACK]); 113 push_greys(pq, bitmap, w, h); 114 } else { 115 pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_GREY]); 116 w /= 2; 117 h /= 2; 118 level++; 119 encode_block(bitmap, w, h, level, pq); 120 encode_block(bitmap + w, w, h, level, pq); 121 encode_block(bitmap + h * XFACE_WIDTH, w, h, level, pq); 122 encode_block(bitmap + w + h * XFACE_WIDTH, w, h, level, pq); 123 } 124} 125 126static av_cold int xface_encode_init(AVCodecContext *avctx) 127{ 128 avctx->coded_frame = av_frame_alloc(); 129 if (!avctx->coded_frame) 130 return AVERROR(ENOMEM); 131 avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I; 132 133 return 0; 134} 135 136static void push_integer(BigInt *b, const ProbRange *prange) 137{ 138 uint8_t r; 139 140 ff_big_div(b, prange->range, &r); 141 ff_big_mul(b, 0); 142 ff_big_add(b, r + prange->offset); 143} 144 145static int xface_encode_frame(AVCodecContext *avctx, AVPacket *pkt, 146 const AVFrame *frame, int *got_packet) 147{ 148 XFaceContext *xface = avctx->priv_data; 149 ProbRangesQueue pq = {{ 0 }, 0}; 150 uint8_t bitmap_copy[XFACE_PIXELS]; 151 BigInt b = {0}; 152 int i, j, k, ret = 0; 153 const uint8_t *buf; 154 uint8_t *p; 155 char intbuf[XFACE_MAX_DIGITS]; 156 157 if (avctx->width || avctx->height) { 158 if (avctx->width != XFACE_WIDTH || avctx->height != XFACE_HEIGHT) { 159 av_log(avctx, AV_LOG_ERROR, 160 "Size value %dx%d not supported, only accepts a size of %dx%d\n", 161 avctx->width, avctx->height, XFACE_WIDTH, XFACE_HEIGHT); 162 return AVERROR(EINVAL); 163 } 164 } 165 avctx->width = XFACE_WIDTH; 166 avctx->height = XFACE_HEIGHT; 167 168 /* convert image from MONOWHITE to 1=black 0=white bitmap */ 169 buf = frame->data[0]; 170 i = j = 0; 171 do { 172 for (k = 0; k < 8; k++) 173 xface->bitmap[i++] = (buf[j]>>(7-k))&1; 174 if (++j == XFACE_WIDTH/8) { 175 buf += frame->linesize[0]; 176 j = 0; 177 } 178 } while (i < XFACE_PIXELS); 179 180 /* create a copy of bitmap */ 181 memcpy(bitmap_copy, xface->bitmap, XFACE_PIXELS); 182 ff_xface_generate_face(xface->bitmap, bitmap_copy); 183 184 encode_block(xface->bitmap, 16, 16, 0, &pq); 185 encode_block(xface->bitmap + 16, 16, 16, 0, &pq); 186 encode_block(xface->bitmap + 32, 16, 16, 0, &pq); 187 encode_block(xface->bitmap + XFACE_WIDTH * 16, 16, 16, 0, &pq); 188 encode_block(xface->bitmap + XFACE_WIDTH * 16 + 16, 16, 16, 0, &pq); 189 encode_block(xface->bitmap + XFACE_WIDTH * 16 + 32, 16, 16, 0, &pq); 190 encode_block(xface->bitmap + XFACE_WIDTH * 32, 16, 16, 0, &pq); 191 encode_block(xface->bitmap + XFACE_WIDTH * 32 + 16, 16, 16, 0, &pq); 192 encode_block(xface->bitmap + XFACE_WIDTH * 32 + 32, 16, 16, 0, &pq); 193 194 while (pq.prob_ranges_idx > 0) 195 push_integer(&b, pq.prob_ranges[--pq.prob_ranges_idx]); 196 197 /* write the inverted big integer in b to intbuf */ 198 i = 0; 199 while (b.nb_words) { 200 uint8_t r; 201 ff_big_div(&b, XFACE_PRINTS, &r); 202 intbuf[i++] = r + XFACE_FIRST_PRINT; 203 } 204 205 if ((ret = ff_alloc_packet2(avctx, pkt, i+2)) < 0) 206 return ret; 207 208 /* revert the number, and close the buffer */ 209 p = pkt->data; 210 while (--i >= 0) 211 *(p++) = intbuf[i]; 212 *(p++) = '\n'; 213 *(p++) = 0; 214 215 pkt->flags |= AV_PKT_FLAG_KEY; 216 *got_packet = 1; 217 218 return 0; 219} 220 221static av_cold int xface_encode_close(AVCodecContext *avctx) 222{ 223 av_freep(&avctx->coded_frame); 224 225 return 0; 226} 227 228AVCodec ff_xface_encoder = { 229 .name = "xface", 230 .long_name = NULL_IF_CONFIG_SMALL("X-face image"), 231 .type = AVMEDIA_TYPE_VIDEO, 232 .id = AV_CODEC_ID_XFACE, 233 .priv_data_size = sizeof(XFaceContext), 234 .init = xface_encode_init, 235 .close = xface_encode_close, 236 .encode2 = xface_encode_frame, 237 .pix_fmts = (const enum PixelFormat[]) { AV_PIX_FMT_MONOWHITE, AV_PIX_FMT_NONE }, 238}; 239