2 * Copyright (c) 1990 James Ashton - Sydney University
3 * Copyright (c) 2012 Stefano Sabatini
5 * This file is part of FFmpeg.
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.
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.
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
24 * X-Face decoder, based on libcompface, by James Ashton.
27 #include "libavutil/pixdesc.h"
29 #include "bytestream.h"
33 static int pop_integer(BigInt *b, const ProbRange *pranges)
38 /* extract the last byte into r, and shift right b by 8 bits */
42 while (r < pranges->offset || r >= pranges->range + pranges->offset) {
46 ff_big_mul(b, pranges->range);
47 ff_big_add(b, r - pranges->offset);
51 static void pop_greys(BigInt *b, char *bitmap, int w, int h)
56 pop_greys(b, bitmap, w, h);
57 pop_greys(b, bitmap + w, w, h);
58 pop_greys(b, bitmap + XFACE_WIDTH * h, w, h);
59 pop_greys(b, bitmap + XFACE_WIDTH * h + w, w, h);
61 w = pop_integer(b, ff_xface_probranges_2x2);
62 if (w & 1) bitmap[0] = 1;
63 if (w & 2) bitmap[1] = 1;
64 if (w & 4) bitmap[XFACE_WIDTH] = 1;
65 if (w & 8) bitmap[XFACE_WIDTH + 1] = 1;
69 static void decode_block(BigInt *b, char *bitmap, int w, int h, int level)
71 switch (pop_integer(b, &ff_xface_probranges_per_level[level][0])) {
72 case XFACE_COLOR_WHITE:
74 case XFACE_COLOR_BLACK:
75 pop_greys(b, bitmap, w, h);
81 decode_block(b, bitmap, w, h, level);
82 decode_block(b, bitmap + w, w, h, level);
83 decode_block(b, bitmap + h * XFACE_WIDTH, w, h, level);
84 decode_block(b, bitmap + w + h * XFACE_WIDTH, w, h, level);
89 typedef struct XFaceContext {
91 uint8_t bitmap[XFACE_PIXELS]; ///< image used internally for decoding
94 static av_cold int xface_decode_init(AVCodecContext *avctx)
96 XFaceContext *xface = avctx->priv_data;
98 avcodec_get_frame_defaults(&xface->frame);
100 if (avctx->width || avctx->height) {
101 if (avctx->width != XFACE_WIDTH || avctx->height != XFACE_HEIGHT) {
102 av_log(avctx, AV_LOG_ERROR,
103 "Size value %dx%d not supported, only accepts a size of %dx%d\n",
104 avctx->width, avctx->height, XFACE_WIDTH, XFACE_HEIGHT);
105 return AVERROR(EINVAL);
109 avctx->width = XFACE_WIDTH;
110 avctx->height = XFACE_HEIGHT;
111 avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
116 static av_cold int xface_decode_close(AVCodecContext *avctx)
118 XFaceContext *xface = avctx->priv_data;
120 if (xface->frame.data[0])
121 avctx->release_buffer(avctx, &xface->frame);
126 static int xface_decode_frame(AVCodecContext *avctx,
127 void *data, int *got_frame,
130 XFaceContext *xface = avctx->priv_data;
137 if (xface->frame.data[0])
138 avctx->release_buffer(avctx, &xface->frame);
139 xface->frame.data[0] = NULL;
140 if ((ret = ff_get_buffer(avctx, &xface->frame)) < 0)
142 xface->frame.reference = 0;
144 for (i = 0, k = 0; avpkt->data[i] && i < avpkt->size; i++) {
147 /* ignore invalid digits */
148 if (c < XFACE_FIRST_PRINT || c > XFACE_LAST_PRINT)
151 if (++k > XFACE_MAX_DIGITS) {
152 av_log(avctx, AV_LOG_WARNING,
153 "Buffer is longer than expected, truncating at byte %d\n", i);
156 ff_big_mul(&b, XFACE_PRINTS);
157 ff_big_add(&b, c - XFACE_FIRST_PRINT);
160 /* decode image and put it in bitmap */
161 memset(xface->bitmap, 0, XFACE_PIXELS);
163 decode_block(&b, buf, 16, 16, 0);
164 decode_block(&b, buf + 16, 16, 16, 0);
165 decode_block(&b, buf + 32, 16, 16, 0);
166 decode_block(&b, buf + XFACE_WIDTH * 16, 16, 16, 0);
167 decode_block(&b, buf + XFACE_WIDTH * 16 + 16, 16, 16, 0);
168 decode_block(&b, buf + XFACE_WIDTH * 16 + 32, 16, 16, 0);
169 decode_block(&b, buf + XFACE_WIDTH * 32 , 16, 16, 0);
170 decode_block(&b, buf + XFACE_WIDTH * 32 + 16, 16, 16, 0);
171 decode_block(&b, buf + XFACE_WIDTH * 32 + 32, 16, 16, 0);
173 ff_xface_generate_face(xface->bitmap, xface->bitmap);
175 /* convert image from 1=black 0=white bitmap to MONOWHITE */
176 buf = xface->frame.data[0];
177 for (i = 0, j = 0, k = 0, byte = 0; i < XFACE_PIXELS; i++) {
178 byte += xface->bitmap[i];
186 if (j == XFACE_WIDTH/8) {
188 buf += xface->frame.linesize[0];
193 *(AVFrame*)data = xface->frame;
198 AVCodec ff_xface_decoder = {
200 .type = AVMEDIA_TYPE_VIDEO,
201 .id = AV_CODEC_ID_XFACE,
202 .priv_data_size = sizeof(XFaceContext),
203 .init = xface_decode_init,
204 .close = xface_decode_close,
205 .decode = xface_decode_frame,
206 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_MONOWHITE, AV_PIX_FMT_NONE },
207 .long_name = NULL_IF_CONFIG_SMALL("X-face image"),