| 1 | /* |
| 2 | * PC Paintbrush PCX (.pcx) image decoder |
| 3 | * Copyright (c) 2007, 2008 Ivo van Poorten |
| 4 | * |
| 5 | * This decoder does not support CGA palettes. I am unable to find samples |
| 6 | * and Netpbm cannot generate them. |
| 7 | * |
| 8 | * This file is part of FFmpeg. |
| 9 | * |
| 10 | * FFmpeg is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU Lesser General Public |
| 12 | * License as published by the Free Software Foundation; either |
| 13 | * version 2.1 of the License, or (at your option) any later version. |
| 14 | * |
| 15 | * FFmpeg is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * Lesser General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU Lesser General Public |
| 21 | * License along with FFmpeg; if not, write to the Free Software |
| 22 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 23 | */ |
| 24 | |
| 25 | #include "libavutil/imgutils.h" |
| 26 | #include "avcodec.h" |
| 27 | #include "bytestream.h" |
| 28 | #include "get_bits.h" |
| 29 | #include "internal.h" |
| 30 | |
| 31 | static void pcx_rle_decode(GetByteContext *gb, |
| 32 | uint8_t *dst, |
| 33 | unsigned int bytes_per_scanline, |
| 34 | int compressed) |
| 35 | { |
| 36 | unsigned int i = 0; |
| 37 | unsigned char run, value; |
| 38 | |
| 39 | if (compressed) { |
| 40 | while (i < bytes_per_scanline && bytestream2_get_bytes_left(gb)>0) { |
| 41 | run = 1; |
| 42 | value = bytestream2_get_byte(gb); |
| 43 | if (value >= 0xc0 && bytestream2_get_bytes_left(gb)>0) { |
| 44 | run = value & 0x3f; |
| 45 | value = bytestream2_get_byte(gb); |
| 46 | } |
| 47 | while (i < bytes_per_scanline && run--) |
| 48 | dst[i++] = value; |
| 49 | } |
| 50 | } else { |
| 51 | bytestream2_get_buffer(gb, dst, bytes_per_scanline); |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen) |
| 56 | { |
| 57 | int i; |
| 58 | |
| 59 | pallen = FFMIN(pallen, bytestream2_get_bytes_left(gb) / 3); |
| 60 | for (i = 0; i < pallen; i++) |
| 61 | *dst++ = 0xFF000000 | bytestream2_get_be24u(gb); |
| 62 | if (pallen < 256) |
| 63 | memset(dst, 0, (256 - pallen) * sizeof(*dst)); |
| 64 | } |
| 65 | |
| 66 | static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, |
| 67 | AVPacket *avpkt) |
| 68 | { |
| 69 | GetByteContext gb; |
| 70 | AVFrame * const p = data; |
| 71 | int compressed, xmin, ymin, xmax, ymax; |
| 72 | int ret; |
| 73 | unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x, |
| 74 | bytes_per_scanline; |
| 75 | uint8_t *ptr, *scanline; |
| 76 | |
| 77 | if (avpkt->size < 128) |
| 78 | return AVERROR_INVALIDDATA; |
| 79 | |
| 80 | bytestream2_init(&gb, avpkt->data, avpkt->size); |
| 81 | |
| 82 | if (bytestream2_get_byteu(&gb) != 0x0a || bytestream2_get_byteu(&gb) > 5) { |
| 83 | av_log(avctx, AV_LOG_ERROR, "this is not PCX encoded data\n"); |
| 84 | return AVERROR_INVALIDDATA; |
| 85 | } |
| 86 | |
| 87 | compressed = bytestream2_get_byteu(&gb); |
| 88 | bits_per_pixel = bytestream2_get_byteu(&gb); |
| 89 | xmin = bytestream2_get_le16u(&gb); |
| 90 | ymin = bytestream2_get_le16u(&gb); |
| 91 | xmax = bytestream2_get_le16u(&gb); |
| 92 | ymax = bytestream2_get_le16u(&gb); |
| 93 | avctx->sample_aspect_ratio.num = bytestream2_get_le16u(&gb); |
| 94 | avctx->sample_aspect_ratio.den = bytestream2_get_le16u(&gb); |
| 95 | |
| 96 | if (xmax < xmin || ymax < ymin) { |
| 97 | av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n"); |
| 98 | return AVERROR_INVALIDDATA; |
| 99 | } |
| 100 | |
| 101 | w = xmax - xmin + 1; |
| 102 | h = ymax - ymin + 1; |
| 103 | |
| 104 | bytestream2_skipu(&gb, 49); |
| 105 | nplanes = bytestream2_get_byteu(&gb); |
| 106 | bytes_per_line = bytestream2_get_le16u(&gb); |
| 107 | bytes_per_scanline = nplanes * bytes_per_line; |
| 108 | |
| 109 | if (bytes_per_scanline < (w * bits_per_pixel * nplanes + 7) / 8 || |
| 110 | (!compressed && bytes_per_scanline > bytestream2_get_bytes_left(&gb) / h)) { |
| 111 | av_log(avctx, AV_LOG_ERROR, "PCX data is corrupted\n"); |
| 112 | return AVERROR_INVALIDDATA; |
| 113 | } |
| 114 | |
| 115 | switch ((nplanes << 8) + bits_per_pixel) { |
| 116 | case 0x0308: |
| 117 | avctx->pix_fmt = AV_PIX_FMT_RGB24; |
| 118 | break; |
| 119 | case 0x0108: |
| 120 | case 0x0104: |
| 121 | case 0x0102: |
| 122 | case 0x0101: |
| 123 | case 0x0401: |
| 124 | case 0x0301: |
| 125 | case 0x0201: |
| 126 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
| 127 | break; |
| 128 | default: |
| 129 | av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n"); |
| 130 | return AVERROR_INVALIDDATA; |
| 131 | } |
| 132 | |
| 133 | bytestream2_skipu(&gb, 60); |
| 134 | |
| 135 | if ((ret = ff_set_dimensions(avctx, w, h)) < 0) |
| 136 | return ret; |
| 137 | |
| 138 | if ((ret = ff_get_buffer(avctx, p, 0)) < 0) |
| 139 | return ret; |
| 140 | |
| 141 | p->pict_type = AV_PICTURE_TYPE_I; |
| 142 | |
| 143 | ptr = p->data[0]; |
| 144 | stride = p->linesize[0]; |
| 145 | |
| 146 | scanline = av_malloc(bytes_per_scanline + FF_INPUT_BUFFER_PADDING_SIZE); |
| 147 | if (!scanline) |
| 148 | return AVERROR(ENOMEM); |
| 149 | |
| 150 | if (nplanes == 3 && bits_per_pixel == 8) { |
| 151 | for (y = 0; y < h; y++) { |
| 152 | pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed); |
| 153 | |
| 154 | for (x = 0; x < w; x++) { |
| 155 | ptr[3 * x] = scanline[x]; |
| 156 | ptr[3 * x + 1] = scanline[x + bytes_per_line]; |
| 157 | ptr[3 * x + 2] = scanline[x + (bytes_per_line << 1)]; |
| 158 | } |
| 159 | |
| 160 | ptr += stride; |
| 161 | } |
| 162 | } else if (nplanes == 1 && bits_per_pixel == 8) { |
| 163 | int palstart = avpkt->size - 769; |
| 164 | |
| 165 | if (avpkt->size < 769) { |
| 166 | av_log(avctx, AV_LOG_ERROR, "File is too short\n"); |
| 167 | ret = avctx->err_recognition & AV_EF_EXPLODE ? |
| 168 | AVERROR_INVALIDDATA : avpkt->size; |
| 169 | goto end; |
| 170 | } |
| 171 | |
| 172 | for (y = 0; y < h; y++, ptr += stride) { |
| 173 | pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed); |
| 174 | memcpy(ptr, scanline, w); |
| 175 | } |
| 176 | |
| 177 | if (bytestream2_tell(&gb) != palstart) { |
| 178 | av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n"); |
| 179 | bytestream2_seek(&gb, palstart, SEEK_SET); |
| 180 | } |
| 181 | if (bytestream2_get_byte(&gb) != 12) { |
| 182 | av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n"); |
| 183 | ret = avctx->err_recognition & AV_EF_EXPLODE ? |
| 184 | AVERROR_INVALIDDATA : avpkt->size; |
| 185 | goto end; |
| 186 | } |
| 187 | } else if (nplanes == 1) { /* all packed formats, max. 16 colors */ |
| 188 | GetBitContext s; |
| 189 | |
| 190 | for (y = 0; y < h; y++) { |
| 191 | init_get_bits8(&s, scanline, bytes_per_scanline); |
| 192 | |
| 193 | pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed); |
| 194 | |
| 195 | for (x = 0; x < w; x++) |
| 196 | ptr[x] = get_bits(&s, bits_per_pixel); |
| 197 | ptr += stride; |
| 198 | } |
| 199 | } else { /* planar, 4, 8 or 16 colors */ |
| 200 | int i; |
| 201 | |
| 202 | for (y = 0; y < h; y++) { |
| 203 | pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed); |
| 204 | |
| 205 | for (x = 0; x < w; x++) { |
| 206 | int m = 0x80 >> (x & 7), v = 0; |
| 207 | for (i = nplanes - 1; i >= 0; i--) { |
| 208 | v <<= 1; |
| 209 | v += !!(scanline[i * bytes_per_line + (x >> 3)] & m); |
| 210 | } |
| 211 | ptr[x] = v; |
| 212 | } |
| 213 | ptr += stride; |
| 214 | } |
| 215 | } |
| 216 | |
| 217 | ret = bytestream2_tell(&gb); |
| 218 | if (nplanes == 1 && bits_per_pixel == 8) { |
| 219 | pcx_palette(&gb, (uint32_t *)p->data[1], 256); |
| 220 | ret += 256 * 3; |
| 221 | } else if (bits_per_pixel * nplanes == 1) { |
| 222 | AV_WN32A(p->data[1] , 0xFF000000); |
| 223 | AV_WN32A(p->data[1]+4, 0xFFFFFFFF); |
| 224 | } else if (bits_per_pixel < 8) { |
| 225 | bytestream2_seek(&gb, 16, SEEK_SET); |
| 226 | pcx_palette(&gb, (uint32_t *)p->data[1], 16); |
| 227 | } |
| 228 | |
| 229 | *got_frame = 1; |
| 230 | |
| 231 | end: |
| 232 | av_free(scanline); |
| 233 | return ret; |
| 234 | } |
| 235 | |
| 236 | AVCodec ff_pcx_decoder = { |
| 237 | .name = "pcx", |
| 238 | .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"), |
| 239 | .type = AVMEDIA_TYPE_VIDEO, |
| 240 | .id = AV_CODEC_ID_PCX, |
| 241 | .decode = pcx_decode_frame, |
| 242 | .capabilities = CODEC_CAP_DR1, |
| 243 | }; |