1/* 2 * Pictor/PC Paint decoder 3 * Copyright (c) 2010 Peter Ross <pross@xvid.org> 4 * 5 * This file is part of Libav. 6 * 7 * Libav 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 * Libav 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 Libav; 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 * Pictor/PC Paint decoder 25 */ 26 27#include "libavutil/imgutils.h" 28#include "avcodec.h" 29#include "bytestream.h" 30#include "cga_data.h" 31 32typedef struct PicContext { 33 AVFrame frame; 34 int width, height; 35 int nb_planes; 36 GetByteContext g; 37} PicContext; 38 39static void picmemset_8bpp(PicContext *s, int value, int run, int *x, int *y) 40{ 41 while (run > 0) { 42 uint8_t *d = s->frame.data[0] + *y * s->frame.linesize[0]; 43 if (*x + run >= s->width) { 44 int n = s->width - *x; 45 memset(d + *x, value, n); 46 run -= n; 47 *x = 0; 48 *y -= 1; 49 if (*y < 0) 50 break; 51 } else { 52 memset(d + *x, value, run); 53 *x += run; 54 break; 55 } 56 } 57} 58 59static void picmemset(PicContext *s, int value, int run, 60 int *x, int *y, int *plane, int bits_per_plane) 61{ 62 uint8_t *d; 63 int shift = *plane * bits_per_plane; 64 int mask = ((1 << bits_per_plane) - 1) << shift; 65 value <<= shift; 66 67 while (run > 0) { 68 int j; 69 for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) { 70 d = s->frame.data[0] + *y * s->frame.linesize[0]; 71 d[*x] |= (value >> j) & mask; 72 *x += 1; 73 if (*x == s->width) { 74 *y -= 1; 75 *x = 0; 76 if (*y < 0) { 77 *y = s->height - 1; 78 *plane += 1; 79 value <<= bits_per_plane; 80 mask <<= bits_per_plane; 81 if (*plane >= s->nb_planes) 82 break; 83 } 84 } 85 } 86 run--; 87 } 88} 89 90static const uint8_t cga_mode45_index[6][4] = { 91 [0] = { 0, 3, 5, 7 }, // mode4, palette#1, low intensity 92 [1] = { 0, 2, 4, 6 }, // mode4, palette#2, low intensity 93 [2] = { 0, 3, 4, 7 }, // mode5, low intensity 94 [3] = { 0, 11, 13, 15 }, // mode4, palette#1, high intensity 95 [4] = { 0, 10, 12, 14 }, // mode4, palette#2, high intensity 96 [5] = { 0, 11, 12, 15 }, // mode5, high intensity 97}; 98 99static int decode_frame(AVCodecContext *avctx, 100 void *data, int *data_size, 101 AVPacket *avpkt) 102{ 103 PicContext *s = avctx->priv_data; 104 uint32_t *palette; 105 int bits_per_plane, bpp, etype, esize, npal, pos_after_pal; 106 int i, x, y, plane, tmp; 107 108 bytestream2_init(&s->g, avpkt->data, avpkt->size); 109 110 if (bytestream2_get_bytes_left(&s->g) < 11) 111 return AVERROR_INVALIDDATA; 112 113 if (bytestream2_get_le16u(&s->g) != 0x1234) 114 return AVERROR_INVALIDDATA; 115 116 s->width = bytestream2_get_le16u(&s->g); 117 s->height = bytestream2_get_le16u(&s->g); 118 bytestream2_skip(&s->g, 4); 119 tmp = bytestream2_get_byteu(&s->g); 120 bits_per_plane = tmp & 0xF; 121 s->nb_planes = (tmp >> 4) + 1; 122 bpp = bits_per_plane * s->nb_planes; 123 if (bits_per_plane > 8 || bpp < 1 || bpp > 32) { 124 av_log_ask_for_sample(s, "unsupported bit depth\n"); 125 return AVERROR_INVALIDDATA; 126 } 127 128 if (bytestream2_peek_byte(&s->g) == 0xFF) { 129 bytestream2_skip(&s->g, 2); 130 etype = bytestream2_get_le16(&s->g); 131 esize = bytestream2_get_le16(&s->g); 132 if (bytestream2_get_bytes_left(&s->g) < esize) 133 return AVERROR_INVALIDDATA; 134 } else { 135 etype = -1; 136 esize = 0; 137 } 138 139 avctx->pix_fmt = PIX_FMT_PAL8; 140 141 if (s->width != avctx->width && s->height != avctx->height) { 142 if (av_image_check_size(s->width, s->height, 0, avctx) < 0) 143 return -1; 144 avcodec_set_dimensions(avctx, s->width, s->height); 145 if (s->frame.data[0]) 146 avctx->release_buffer(avctx, &s->frame); 147 } 148 149 if (avctx->get_buffer(avctx, &s->frame) < 0){ 150 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); 151 return -1; 152 } 153 memset(s->frame.data[0], 0, s->height * s->frame.linesize[0]); 154 s->frame.pict_type = AV_PICTURE_TYPE_I; 155 s->frame.palette_has_changed = 1; 156 157 pos_after_pal = bytestream2_tell(&s->g) + esize; 158 palette = (uint32_t*)s->frame.data[1]; 159 if (etype == 1 && esize > 1 && bytestream2_peek_byte(&s->g) < 6) { 160 int idx = bytestream2_get_byte(&s->g); 161 npal = 4; 162 for (i = 0; i < npal; i++) 163 palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ]; 164 } else if (etype == 2) { 165 npal = FFMIN(esize, 16); 166 for (i = 0; i < npal; i++) { 167 int pal_idx = bytestream2_get_byte(&s->g); 168 palette[i] = ff_cga_palette[FFMIN(pal_idx, 16)]; 169 } 170 } else if (etype == 3) { 171 npal = FFMIN(esize, 16); 172 for (i = 0; i < npal; i++) { 173 int pal_idx = bytestream2_get_byte(&s->g); 174 palette[i] = ff_ega_palette[FFMIN(pal_idx, 63)]; 175 } 176 } else if (etype == 4 || etype == 5) { 177 npal = FFMIN(esize / 3, 256); 178 for (i = 0; i < npal; i++) 179 palette[i] = bytestream2_get_be24(&s->g) << 2; 180 } else { 181 if (bpp == 1) { 182 npal = 2; 183 palette[0] = 0x000000; 184 palette[1] = 0xFFFFFF; 185 } else if (bpp == 2) { 186 npal = 4; 187 for (i = 0; i < npal; i++) 188 palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ]; 189 } else { 190 npal = 16; 191 memcpy(palette, ff_cga_palette, npal * 4); 192 } 193 } 194 // fill remaining palette entries 195 memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4); 196 // skip remaining palette bytes 197 bytestream2_seek(&s->g, pos_after_pal, SEEK_SET); 198 199 x = 0; 200 y = s->height - 1; 201 plane = 0; 202 if (bytestream2_get_le16(&s->g)) { 203 while (bytestream2_get_bytes_left(&s->g) >= 6) { 204 int stop_size, marker, t1, t2; 205 206 t1 = bytestream2_get_bytes_left(&s->g); 207 t2 = bytestream2_get_le16(&s->g); 208 stop_size = t1 - FFMIN(t1, t2); 209 // ignore uncompressed block size 210 bytestream2_skip(&s->g, 2); 211 marker = bytestream2_get_byte(&s->g); 212 213 while (plane < s->nb_planes && 214 bytestream2_get_bytes_left(&s->g) > stop_size) { 215 int run = 1; 216 int val = bytestream2_get_byte(&s->g); 217 if (val == marker) { 218 run = bytestream2_get_byte(&s->g); 219 if (run == 0) 220 run = bytestream2_get_le16(&s->g); 221 val = bytestream2_get_byte(&s->g); 222 } 223 if (!bytestream2_get_bytes_left(&s->g)) 224 break; 225 226 if (bits_per_plane == 8) { 227 picmemset_8bpp(s, val, run, &x, &y); 228 if (y < 0) 229 break; 230 } else { 231 picmemset(s, val, run, &x, &y, &plane, bits_per_plane); 232 } 233 } 234 } 235 } else { 236 av_log_ask_for_sample(s, "uncompressed image\n"); 237 return avpkt->size; 238 } 239 240 *data_size = sizeof(AVFrame); 241 *(AVFrame*)data = s->frame; 242 return avpkt->size; 243} 244 245static av_cold int decode_end(AVCodecContext *avctx) 246{ 247 PicContext *s = avctx->priv_data; 248 if (s->frame.data[0]) 249 avctx->release_buffer(avctx, &s->frame); 250 return 0; 251} 252 253AVCodec ff_pictor_decoder = { 254 .name = "pictor", 255 .type = AVMEDIA_TYPE_VIDEO, 256 .id = CODEC_ID_PICTOR, 257 .priv_data_size = sizeof(PicContext), 258 .close = decode_end, 259 .decode = decode_frame, 260 .capabilities = CODEC_CAP_DR1, 261 .long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"), 262}; 263