2 * PC Paintbrush PCX (.pcx) image decoder
3 * Copyright (c) 2007, 2008 Ivo van Poorten
5 * This decoder does not support CGA palettes. I am unable to find samples
6 * and Netpbm cannot generate them.
8 * This file is part of FFmpeg.
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.
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.
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
25 #include "libavutil/imgutils.h"
27 #include "bytestream.h"
31 static void pcx_rle_decode(GetByteContext *gb,
33 unsigned int bytes_per_scanline,
37 unsigned char run, value;
40 while (i < bytes_per_scanline && bytestream2_get_bytes_left(gb)>0) {
42 value = bytestream2_get_byte(gb);
43 if (value >= 0xc0 && bytestream2_get_bytes_left(gb)>0) {
45 value = bytestream2_get_byte(gb);
47 while (i < bytes_per_scanline && run--)
51 bytestream2_get_buffer(gb, dst, bytes_per_scanline);
55 static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
59 pallen = FFMIN(pallen, bytestream2_get_bytes_left(gb) / 3);
60 for (i = 0; i < pallen; i++)
61 *dst++ = 0xFF000000 | bytestream2_get_be24u(gb);
63 memset(dst, 0, (256 - pallen) * sizeof(*dst));
66 static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
70 AVFrame * const p = data;
71 int compressed, xmin, ymin, xmax, ymax;
73 unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x,
75 uint8_t *ptr, *scanline;
77 if (avpkt->size < 128)
78 return AVERROR_INVALIDDATA;
80 bytestream2_init(&gb, avpkt->data, avpkt->size);
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;
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);
96 if (xmax < xmin || ymax < ymin) {
97 av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n");
98 return AVERROR_INVALIDDATA;
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;
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;
115 switch ((nplanes << 8) + bits_per_pixel) {
117 avctx->pix_fmt = AV_PIX_FMT_RGB24;
126 avctx->pix_fmt = AV_PIX_FMT_PAL8;
129 av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n");
130 return AVERROR_INVALIDDATA;
133 bytestream2_skipu(&gb, 60);
135 if ((ret = av_image_check_size(w, h, 0, avctx)) < 0)
137 if (w != avctx->width || h != avctx->height)
138 avcodec_set_dimensions(avctx, w, h);
139 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
142 p->pict_type = AV_PICTURE_TYPE_I;
145 stride = p->linesize[0];
147 scanline = av_malloc(bytes_per_scanline + FF_INPUT_BUFFER_PADDING_SIZE);
149 return AVERROR(ENOMEM);
151 if (nplanes == 3 && bits_per_pixel == 8) {
152 for (y = 0; y < h; y++) {
153 pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
155 for (x = 0; x < w; x++) {
156 ptr[3 * x] = scanline[x];
157 ptr[3 * x + 1] = scanline[x + bytes_per_line];
158 ptr[3 * x + 2] = scanline[x + (bytes_per_line << 1)];
163 } else if (nplanes == 1 && bits_per_pixel == 8) {
164 int palstart = avpkt->size - 769;
166 if (avpkt->size < 769) {
167 av_log(avctx, AV_LOG_ERROR, "File is too short\n");
168 ret = avctx->err_recognition & AV_EF_EXPLODE ?
169 AVERROR_INVALIDDATA : avpkt->size;
173 for (y = 0; y < h; y++, ptr += stride) {
174 pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
175 memcpy(ptr, scanline, w);
178 if (bytestream2_tell(&gb) != palstart) {
179 av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n");
180 bytestream2_seek(&gb, palstart, SEEK_SET);
182 if (bytestream2_get_byte(&gb) != 12) {
183 av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
184 ret = avctx->err_recognition & AV_EF_EXPLODE ?
185 AVERROR_INVALIDDATA : avpkt->size;
188 } else if (nplanes == 1) { /* all packed formats, max. 16 colors */
191 for (y = 0; y < h; y++) {
192 init_get_bits8(&s, scanline, bytes_per_scanline);
194 pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
196 for (x = 0; x < w; x++)
197 ptr[x] = get_bits(&s, bits_per_pixel);
200 } else { /* planar, 4, 8 or 16 colors */
203 for (y = 0; y < h; y++) {
204 pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
206 for (x = 0; x < w; x++) {
207 int m = 0x80 >> (x & 7), v = 0;
208 for (i = nplanes - 1; i >= 0; i--) {
210 v += !!(scanline[i * bytes_per_line + (x >> 3)] & m);
218 ret = bytestream2_tell(&gb);
219 if (nplanes == 1 && bits_per_pixel == 8) {
220 pcx_palette(&gb, (uint32_t *)p->data[1], 256);
222 } else if (bits_per_pixel * nplanes == 1) {
223 AV_WN32A(p->data[1] , 0xFF000000);
224 AV_WN32A(p->data[1]+4, 0xFFFFFFFF);
225 } else if (bits_per_pixel < 8) {
226 bytestream2_seek(&gb, 16, SEEK_SET);
227 pcx_palette(&gb, (uint32_t *)p->data[1], 16);
237 AVCodec ff_pcx_decoder = {
239 .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
240 .type = AVMEDIA_TYPE_VIDEO,
241 .id = AV_CODEC_ID_PCX,
242 .decode = pcx_decode_frame,
243 .capabilities = CODEC_CAP_DR1,