1/* 2 * Pictor/PC Paint decoder 3 * Copyright (c) 2010 Peter Ross <pross@xvid.org> 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 * 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#include "internal.h" 32 33typedef struct PicContext { 34 int width, height; 35 int nb_planes; 36 GetByteContext g; 37} PicContext; 38 39static void picmemset_8bpp(PicContext *s, AVFrame *frame, int value, int run, 40 int *x, int *y) 41{ 42 while (run > 0) { 43 uint8_t *d = frame->data[0] + *y * frame->linesize[0]; 44 if (*x + run >= s->width) { 45 int n = s->width - *x; 46 memset(d + *x, value, n); 47 run -= n; 48 *x = 0; 49 *y -= 1; 50 if (*y < 0) 51 break; 52 } else { 53 memset(d + *x, value, run); 54 *x += run; 55 break; 56 } 57 } 58} 59 60static void picmemset(PicContext *s, AVFrame *frame, int value, int run, 61 int *x, int *y, int *plane, int bits_per_plane) 62{ 63 uint8_t *d; 64 int shift = *plane * bits_per_plane; 65 int mask = ((1 << bits_per_plane) - 1) << shift; 66 value <<= shift; 67 68 while (run > 0) { 69 int j; 70 for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) { 71 d = frame->data[0] + *y * frame->linesize[0]; 72 d[*x] |= (value >> j) & mask; 73 *x += 1; 74 if (*x == s->width) { 75 *y -= 1; 76 *x = 0; 77 if (*y < 0) { 78 *y = s->height - 1; 79 *plane += 1; 80 value <<= bits_per_plane; 81 mask <<= bits_per_plane; 82 if (*plane >= s->nb_planes) 83 break; 84 } 85 } 86 } 87 run--; 88 } 89} 90 91static const uint8_t cga_mode45_index[6][4] = { 92 [0] = { 0, 3, 5, 7 }, // mode4, palette#1, low intensity 93 [1] = { 0, 2, 4, 6 }, // mode4, palette#2, low intensity 94 [2] = { 0, 3, 4, 7 }, // mode5, low intensity 95 [3] = { 0, 11, 13, 15 }, // mode4, palette#1, high intensity 96 [4] = { 0, 10, 12, 14 }, // mode4, palette#2, high intensity 97 [5] = { 0, 11, 12, 15 }, // mode5, high intensity 98}; 99 100static int decode_frame(AVCodecContext *avctx, 101 void *data, int *got_frame, 102 AVPacket *avpkt) 103{ 104 PicContext *s = avctx->priv_data; 105 AVFrame *frame = data; 106 uint32_t *palette; 107 int bits_per_plane, bpp, etype, esize, npal, pos_after_pal; 108 int i, x, y, plane, tmp, ret, val; 109 110 bytestream2_init(&s->g, avpkt->data, avpkt->size); 111 112 if (bytestream2_get_bytes_left(&s->g) < 11) 113 return AVERROR_INVALIDDATA; 114 115 if (bytestream2_get_le16u(&s->g) != 0x1234) 116 return AVERROR_INVALIDDATA; 117 118 s->width = bytestream2_get_le16u(&s->g); 119 s->height = bytestream2_get_le16u(&s->g); 120 bytestream2_skip(&s->g, 4); 121 tmp = bytestream2_get_byteu(&s->g); 122 bits_per_plane = tmp & 0xF; 123 s->nb_planes = (tmp >> 4) + 1; 124 bpp = bits_per_plane * s->nb_planes; 125 if (bits_per_plane > 8 || bpp < 1 || bpp > 32) { 126 avpriv_request_sample(avctx, "Unsupported bit depth"); 127 return AVERROR_PATCHWELCOME; 128 } 129 130 if (bytestream2_peek_byte(&s->g) == 0xFF || bpp == 1 || bpp == 4 || bpp == 8) { 131 bytestream2_skip(&s->g, 2); 132 etype = bytestream2_get_le16(&s->g); 133 esize = bytestream2_get_le16(&s->g); 134 if (bytestream2_get_bytes_left(&s->g) < esize) 135 return AVERROR_INVALIDDATA; 136 } else { 137 etype = -1; 138 esize = 0; 139 } 140 141 avctx->pix_fmt = AV_PIX_FMT_PAL8; 142 143 if (av_image_check_size(s->width, s->height, 0, avctx) < 0) 144 return -1; 145 if (s->width != avctx->width && s->height != avctx->height) { 146 ret = ff_set_dimensions(avctx, s->width, s->height); 147 if (ret < 0) 148 return ret; 149 } 150 151 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) 152 return ret; 153 memset(frame->data[0], 0, s->height * frame->linesize[0]); 154 frame->pict_type = AV_PICTURE_TYPE_I; 155 frame->palette_has_changed = 1; 156 157 pos_after_pal = bytestream2_tell(&s->g) + esize; 158 palette = (uint32_t*)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, 15)]; 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 palette[i] |= 0xFFU << 24 | palette[i] >> 6 & 0x30303; 181 } 182 } else { 183 if (bpp == 1) { 184 npal = 2; 185 palette[0] = 0xFF000000; 186 palette[1] = 0xFFFFFFFF; 187 } else if (bpp == 2) { 188 npal = 4; 189 for (i = 0; i < npal; i++) 190 palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ]; 191 } else { 192 npal = 16; 193 memcpy(palette, ff_cga_palette, npal * 4); 194 } 195 } 196 // fill remaining palette entries 197 memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4); 198 // skip remaining palette bytes 199 bytestream2_seek(&s->g, pos_after_pal, SEEK_SET); 200 201 val = 0; 202 y = s->height - 1; 203 if (bytestream2_get_le16(&s->g)) { 204 x = 0; 205 plane = 0; 206 while (bytestream2_get_bytes_left(&s->g) >= 6) { 207 int stop_size, marker, t1, t2; 208 209 t1 = bytestream2_get_bytes_left(&s->g); 210 t2 = bytestream2_get_le16(&s->g); 211 stop_size = t1 - FFMIN(t1, t2); 212 // ignore uncompressed block size 213 bytestream2_skip(&s->g, 2); 214 marker = bytestream2_get_byte(&s->g); 215 216 while (plane < s->nb_planes && 217 bytestream2_get_bytes_left(&s->g) > stop_size) { 218 int run = 1; 219 val = bytestream2_get_byte(&s->g); 220 if (val == marker) { 221 run = bytestream2_get_byte(&s->g); 222 if (run == 0) 223 run = bytestream2_get_le16(&s->g); 224 val = bytestream2_get_byte(&s->g); 225 } 226 if (!bytestream2_get_bytes_left(&s->g)) 227 break; 228 229 if (bits_per_plane == 8) { 230 picmemset_8bpp(s, frame, val, run, &x, &y); 231 if (y < 0) 232 goto finish; 233 } else { 234 picmemset(s, frame, val, run, &x, &y, &plane, bits_per_plane); 235 } 236 } 237 } 238 239 if (x < avctx->width) { 240 int run = (y + 1) * avctx->width - x; 241 if (bits_per_plane == 8) 242 picmemset_8bpp(s, frame, val, run, &x, &y); 243 else 244 picmemset(s, frame, val, run / (8 / bits_per_plane), &x, &y, &plane, bits_per_plane); 245 } 246 } else { 247 while (y >= 0 && bytestream2_get_bytes_left(&s->g) > 0) { 248 memcpy(frame->data[0] + y * frame->linesize[0], s->g.buffer, FFMIN(avctx->width, bytestream2_get_bytes_left(&s->g))); 249 bytestream2_skip(&s->g, avctx->width); 250 y--; 251 } 252 } 253finish: 254 255 *got_frame = 1; 256 return avpkt->size; 257} 258 259AVCodec ff_pictor_decoder = { 260 .name = "pictor", 261 .long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"), 262 .type = AVMEDIA_TYPE_VIDEO, 263 .id = AV_CODEC_ID_PICTOR, 264 .priv_data_size = sizeof(PicContext), 265 .decode = decode_frame, 266 .capabilities = CODEC_CAP_DR1, 267}; 268