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, uint8_t *dst,
32 unsigned int bytes_per_scanline, int compressed)
35 unsigned char run, value;
38 while (i<bytes_per_scanline) {
40 value = bytestream2_get_byte(gb);
43 value = bytestream2_get_byte(gb);
45 while (i<bytes_per_scanline && run--)
49 bytestream2_get_buffer(gb, dst, bytes_per_scanline);
53 static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
57 pallen = FFMIN(pallen, bytestream2_get_bytes_left(gb) / 3);
58 for (i=0; i<pallen; i++)
59 *dst++ = 0xFF000000 | bytestream2_get_be24u(gb);
61 memset(dst, 0, (256 - pallen) * sizeof(*dst));
64 static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
67 AVFrame * const p = data;
68 int compressed, xmin, ymin, xmax, ymax, ret;
69 unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x,
71 uint8_t *ptr, *scanline;
73 if (avpkt->size < 128)
74 return AVERROR_INVALIDDATA;
76 bytestream2_init(&gb, avpkt->data, avpkt->size);
78 if (bytestream2_get_byteu(&gb) != 0x0a || bytestream2_get_byteu(&gb) > 5) {
79 av_log(avctx, AV_LOG_ERROR, "this is not PCX encoded data\n");
80 return AVERROR_INVALIDDATA;
83 compressed = bytestream2_get_byteu(&gb);
84 bits_per_pixel = bytestream2_get_byteu(&gb);
85 xmin = bytestream2_get_le16u(&gb);
86 ymin = bytestream2_get_le16u(&gb);
87 xmax = bytestream2_get_le16u(&gb);
88 ymax = bytestream2_get_le16u(&gb);
89 avctx->sample_aspect_ratio.num = bytestream2_get_le16u(&gb);
90 avctx->sample_aspect_ratio.den = bytestream2_get_le16u(&gb);
92 if (xmax < xmin || ymax < ymin) {
93 av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n");
94 return AVERROR_INVALIDDATA;
100 bytestream2_skipu(&gb, 49);
101 nplanes = bytestream2_get_byteu(&gb);
102 bytes_per_line = bytestream2_get_le16u(&gb);
103 bytes_per_scanline = nplanes * bytes_per_line;
105 if (bytes_per_scanline < (w * bits_per_pixel * nplanes + 7) / 8) {
106 av_log(avctx, AV_LOG_ERROR, "PCX data is corrupted\n");
107 return AVERROR_INVALIDDATA;
110 switch ((nplanes<<8) + bits_per_pixel) {
112 avctx->pix_fmt = AV_PIX_FMT_RGB24;
121 avctx->pix_fmt = AV_PIX_FMT_PAL8;
124 av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n");
125 return AVERROR_INVALIDDATA;
128 bytestream2_skipu(&gb, 60);
130 if ((ret = av_image_check_size(w, h, 0, avctx)) < 0)
132 if (w != avctx->width || h != avctx->height)
133 avcodec_set_dimensions(avctx, w, h);
134 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
137 p->pict_type = AV_PICTURE_TYPE_I;
140 stride = p->linesize[0];
142 scanline = av_malloc(bytes_per_scanline + FF_INPUT_BUFFER_PADDING_SIZE);
144 return AVERROR(ENOMEM);
146 if (nplanes == 3 && bits_per_pixel == 8) {
147 for (y=0; y<h; y++) {
148 pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
150 for (x=0; x<w; x++) {
151 ptr[3*x ] = scanline[x ];
152 ptr[3*x+1] = scanline[x+ bytes_per_line ];
153 ptr[3*x+2] = scanline[x+(bytes_per_line<<1)];
159 } else if (nplanes == 1 && bits_per_pixel == 8) {
160 int palstart = avpkt->size - 769;
162 for (y=0; y<h; y++, ptr+=stride) {
163 pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
164 memcpy(ptr, scanline, w);
167 if (bytestream2_tell(&gb) != palstart) {
168 av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n");
169 bytestream2_seek(&gb, palstart, SEEK_SET);
171 if (bytestream2_get_byte(&gb) != 12) {
172 av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
173 ret = AVERROR_INVALIDDATA;
177 } else if (nplanes == 1) { /* all packed formats, max. 16 colors */
180 for (y=0; y<h; y++) {
181 init_get_bits8(&s, scanline, bytes_per_scanline);
183 pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
186 ptr[x] = get_bits(&s, bits_per_pixel);
190 } else { /* planar, 4, 8 or 16 colors */
193 for (y=0; y<h; y++) {
194 pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
196 for (x=0; x<w; x++) {
197 int m = 0x80 >> (x&7), v = 0;
198 for (i=nplanes - 1; i>=0; i--) {
200 v += !!(scanline[i*bytes_per_line + (x>>3)] & m);
208 ret = bytestream2_tell(&gb);
209 if (nplanes == 1 && bits_per_pixel == 8) {
210 pcx_palette(&gb, (uint32_t *) p->data[1], 256);
212 } else if (bits_per_pixel * nplanes == 1) {
213 AV_WN32A(p->data[1] , 0xFF000000);
214 AV_WN32A(p->data[1]+4, 0xFFFFFFFF);
215 } else if (bits_per_pixel < 8) {
216 bytestream2_seek(&gb, 16, SEEK_SET);
217 pcx_palette(&gb, (uint32_t *) p->data[1], 16);
227 AVCodec ff_pcx_decoder = {
229 .type = AVMEDIA_TYPE_VIDEO,
230 .id = AV_CODEC_ID_PCX,
231 .decode = pcx_decode_frame,
232 .capabilities = CODEC_CAP_DR1,
233 .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),