blob: bfb9fb9ece88c8c501aa7fce5b1091f53f4072ce
| 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 | #include "libavutil/avassert.h" |
| 31 | |
| 32 | typedef struct XFaceContext { |
| 33 | AVClass *class; |
| 34 | uint8_t bitmap[XFACE_PIXELS]; ///< image used internally for decoding |
| 35 | int max_line_len; ///< max line length for compressed data |
| 36 | int set_header; ///< set X-Face header in the output |
| 37 | } XFaceContext; |
| 38 | |
| 39 | static int all_same(char *bitmap, int w, int h) |
| 40 | { |
| 41 | char val, *row; |
| 42 | int x; |
| 43 | |
| 44 | val = *bitmap; |
| 45 | while (h--) { |
| 46 | row = bitmap; |
| 47 | x = w; |
| 48 | while (x--) |
| 49 | if (*(row++) != val) |
| 50 | return 0; |
| 51 | bitmap += XFACE_WIDTH; |
| 52 | } |
| 53 | return 1; |
| 54 | } |
| 55 | |
| 56 | static int all_black(char *bitmap, int w, int h) |
| 57 | { |
| 58 | if (w > 3) { |
| 59 | w /= 2; |
| 60 | h /= 2; |
| 61 | return (all_black(bitmap, w, h) && all_black(bitmap + w, w, h) && |
| 62 | all_black(bitmap + XFACE_WIDTH * h, w, h) && |
| 63 | all_black(bitmap + XFACE_WIDTH * h + w, w, h)); |
| 64 | } else { |
| 65 | /* at least one pixel in the 2x2 grid is non-zero */ |
| 66 | return *bitmap || *(bitmap + 1) || |
| 67 | *(bitmap + XFACE_WIDTH) || *(bitmap + XFACE_WIDTH + 1); |
| 68 | } |
| 69 | } |
| 70 | |
| 71 | static int all_white(char *bitmap, int w, int h) |
| 72 | { |
| 73 | return *bitmap == 0 && all_same(bitmap, w, h); |
| 74 | } |
| 75 | |
| 76 | typedef struct { |
| 77 | ProbRange prob_ranges[XFACE_PIXELS*2]; |
| 78 | int prob_ranges_idx; |
| 79 | } ProbRangesQueue; |
| 80 | |
| 81 | static inline int pq_push(ProbRangesQueue *pq, const ProbRange *p) |
| 82 | { |
| 83 | if (pq->prob_ranges_idx >= XFACE_PIXELS * 2 - 1) |
| 84 | return -1; |
| 85 | pq->prob_ranges[pq->prob_ranges_idx++] = *p; |
| 86 | return 0; |
| 87 | } |
| 88 | |
| 89 | static void push_greys(ProbRangesQueue *pq, char *bitmap, int w, int h) |
| 90 | { |
| 91 | if (w > 3) { |
| 92 | w /= 2; |
| 93 | h /= 2; |
| 94 | push_greys(pq, bitmap, w, h); |
| 95 | push_greys(pq, bitmap + w, w, h); |
| 96 | push_greys(pq, bitmap + XFACE_WIDTH * h, w, h); |
| 97 | push_greys(pq, bitmap + XFACE_WIDTH * h + w, w, h); |
| 98 | } else { |
| 99 | const ProbRange *p = ff_xface_probranges_2x2 + |
| 100 | *bitmap + |
| 101 | 2 * *(bitmap + 1) + |
| 102 | 4 * *(bitmap + XFACE_WIDTH) + |
| 103 | 8 * *(bitmap + XFACE_WIDTH + 1); |
| 104 | pq_push(pq, p); |
| 105 | } |
| 106 | } |
| 107 | |
| 108 | static void encode_block(char *bitmap, int w, int h, int level, ProbRangesQueue *pq) |
| 109 | { |
| 110 | if (all_white(bitmap, w, h)) { |
| 111 | pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_WHITE]); |
| 112 | } else if (all_black(bitmap, w, h)) { |
| 113 | pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_BLACK]); |
| 114 | push_greys(pq, bitmap, w, h); |
| 115 | } else { |
| 116 | pq_push(pq, &ff_xface_probranges_per_level[level][XFACE_COLOR_GREY]); |
| 117 | w /= 2; |
| 118 | h /= 2; |
| 119 | level++; |
| 120 | encode_block(bitmap, w, h, level, pq); |
| 121 | encode_block(bitmap + w, w, h, level, pq); |
| 122 | encode_block(bitmap + h * XFACE_WIDTH, w, h, level, pq); |
| 123 | encode_block(bitmap + w + h * XFACE_WIDTH, w, h, level, pq); |
| 124 | } |
| 125 | } |
| 126 | |
| 127 | static void push_integer(BigInt *b, const ProbRange *prange) |
| 128 | { |
| 129 | uint8_t r; |
| 130 | |
| 131 | ff_big_div(b, prange->range, &r); |
| 132 | ff_big_mul(b, 0); |
| 133 | ff_big_add(b, r + prange->offset); |
| 134 | } |
| 135 | |
| 136 | static int xface_encode_frame(AVCodecContext *avctx, AVPacket *pkt, |
| 137 | const AVFrame *frame, int *got_packet) |
| 138 | { |
| 139 | XFaceContext *xface = avctx->priv_data; |
| 140 | ProbRangesQueue pq = {{{ 0 }}, 0}; |
| 141 | uint8_t bitmap_copy[XFACE_PIXELS]; |
| 142 | BigInt b = {0}; |
| 143 | int i, j, k, ret = 0; |
| 144 | const uint8_t *buf; |
| 145 | uint8_t *p; |
| 146 | char intbuf[XFACE_MAX_DIGITS]; |
| 147 | |
| 148 | if (avctx->width || avctx->height) { |
| 149 | if (avctx->width != XFACE_WIDTH || avctx->height != XFACE_HEIGHT) { |
| 150 | av_log(avctx, AV_LOG_ERROR, |
| 151 | "Size value %dx%d not supported, only accepts a size of %dx%d\n", |
| 152 | avctx->width, avctx->height, XFACE_WIDTH, XFACE_HEIGHT); |
| 153 | return AVERROR(EINVAL); |
| 154 | } |
| 155 | } |
| 156 | avctx->width = XFACE_WIDTH; |
| 157 | avctx->height = XFACE_HEIGHT; |
| 158 | |
| 159 | /* convert image from MONOWHITE to 1=black 0=white bitmap */ |
| 160 | buf = frame->data[0]; |
| 161 | i = j = 0; |
| 162 | do { |
| 163 | for (k = 0; k < 8; k++) |
| 164 | xface->bitmap[i++] = (buf[j]>>(7-k))&1; |
| 165 | if (++j == XFACE_WIDTH/8) { |
| 166 | buf += frame->linesize[0]; |
| 167 | j = 0; |
| 168 | } |
| 169 | } while (i < XFACE_PIXELS); |
| 170 | |
| 171 | /* create a copy of bitmap */ |
| 172 | memcpy(bitmap_copy, xface->bitmap, XFACE_PIXELS); |
| 173 | ff_xface_generate_face(xface->bitmap, bitmap_copy); |
| 174 | |
| 175 | encode_block(xface->bitmap, 16, 16, 0, &pq); |
| 176 | encode_block(xface->bitmap + 16, 16, 16, 0, &pq); |
| 177 | encode_block(xface->bitmap + 32, 16, 16, 0, &pq); |
| 178 | encode_block(xface->bitmap + XFACE_WIDTH * 16, 16, 16, 0, &pq); |
| 179 | encode_block(xface->bitmap + XFACE_WIDTH * 16 + 16, 16, 16, 0, &pq); |
| 180 | encode_block(xface->bitmap + XFACE_WIDTH * 16 + 32, 16, 16, 0, &pq); |
| 181 | encode_block(xface->bitmap + XFACE_WIDTH * 32, 16, 16, 0, &pq); |
| 182 | encode_block(xface->bitmap + XFACE_WIDTH * 32 + 16, 16, 16, 0, &pq); |
| 183 | encode_block(xface->bitmap + XFACE_WIDTH * 32 + 32, 16, 16, 0, &pq); |
| 184 | |
| 185 | while (pq.prob_ranges_idx > 0) |
| 186 | push_integer(&b, &pq.prob_ranges[--pq.prob_ranges_idx]); |
| 187 | |
| 188 | /* write the inverted big integer in b to intbuf */ |
| 189 | i = 0; |
| 190 | av_assert0(b.nb_words < XFACE_MAX_WORDS); |
| 191 | while (b.nb_words) { |
| 192 | uint8_t r; |
| 193 | ff_big_div(&b, XFACE_PRINTS, &r); |
| 194 | av_assert0(i < sizeof(intbuf)); |
| 195 | intbuf[i++] = r + XFACE_FIRST_PRINT; |
| 196 | } |
| 197 | |
| 198 | if ((ret = ff_alloc_packet2(avctx, pkt, i+2, 0)) < 0) |
| 199 | return ret; |
| 200 | |
| 201 | /* revert the number, and close the buffer */ |
| 202 | p = pkt->data; |
| 203 | while (--i >= 0) |
| 204 | *(p++) = intbuf[i]; |
| 205 | *(p++) = '\n'; |
| 206 | *(p++) = 0; |
| 207 | |
| 208 | pkt->flags |= AV_PKT_FLAG_KEY; |
| 209 | *got_packet = 1; |
| 210 | |
| 211 | return 0; |
| 212 | } |
| 213 | |
| 214 | AVCodec ff_xface_encoder = { |
| 215 | .name = "xface", |
| 216 | .long_name = NULL_IF_CONFIG_SMALL("X-face image"), |
| 217 | .type = AVMEDIA_TYPE_VIDEO, |
| 218 | .id = AV_CODEC_ID_XFACE, |
| 219 | .priv_data_size = sizeof(XFaceContext), |
| 220 | .encode2 = xface_encode_frame, |
| 221 | .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_MONOWHITE, AV_PIX_FMT_NONE }, |
| 222 | .capabilities = AV_CODEC_CAP_INTRA_ONLY, |
| 223 | }; |
| 224 |