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pcx.c
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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 #define PCX_HEADER_SIZE 128
32 
34  uint8_t *dst,
35  unsigned int bytes_per_scanline,
36  int compressed)
37 {
38  unsigned int i = 0;
39  unsigned char run, value;
40 
41  if (bytestream2_get_bytes_left(gb) < 1)
42  return AVERROR_INVALIDDATA;
43 
44  if (compressed) {
45  while (i < bytes_per_scanline && bytestream2_get_bytes_left(gb)>0) {
46  run = 1;
47  value = bytestream2_get_byte(gb);
48  if (value >= 0xc0 && bytestream2_get_bytes_left(gb)>0) {
49  run = value & 0x3f;
50  value = bytestream2_get_byte(gb);
51  }
52  while (i < bytes_per_scanline && run--)
53  dst[i++] = value;
54  }
55  } else {
56  bytestream2_get_buffer(gb, dst, bytes_per_scanline);
57  }
58  return 0;
59 }
60 
61 static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
62 {
63  int i;
64 
65  pallen = FFMIN(pallen, bytestream2_get_bytes_left(gb) / 3);
66  for (i = 0; i < pallen; i++)
67  *dst++ = 0xFF000000 | bytestream2_get_be24u(gb);
68  if (pallen < 256)
69  memset(dst, 0, (256 - pallen) * sizeof(*dst));
70 }
71 
72 static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
73  AVPacket *avpkt)
74 {
75  GetByteContext gb;
76  AVFrame * const p = data;
77  int compressed, xmin, ymin, xmax, ymax;
78  int ret;
79  unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x,
80  bytes_per_scanline;
81  uint8_t *ptr, *scanline;
82 
83  if (avpkt->size < PCX_HEADER_SIZE) {
84  av_log(avctx, AV_LOG_ERROR, "Packet too small\n");
85  return AVERROR_INVALIDDATA;
86  }
87 
88  bytestream2_init(&gb, avpkt->data, avpkt->size);
89 
90  if (bytestream2_get_byteu(&gb) != 0x0a || bytestream2_get_byteu(&gb) > 5) {
91  av_log(avctx, AV_LOG_ERROR, "this is not PCX encoded data\n");
92  return AVERROR_INVALIDDATA;
93  }
94 
95  compressed = bytestream2_get_byteu(&gb);
96  bits_per_pixel = bytestream2_get_byteu(&gb);
97  xmin = bytestream2_get_le16u(&gb);
98  ymin = bytestream2_get_le16u(&gb);
99  xmax = bytestream2_get_le16u(&gb);
100  ymax = bytestream2_get_le16u(&gb);
101  avctx->sample_aspect_ratio.num = bytestream2_get_le16u(&gb);
102  avctx->sample_aspect_ratio.den = bytestream2_get_le16u(&gb);
103 
104  if (xmax < xmin || ymax < ymin) {
105  av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n");
106  return AVERROR_INVALIDDATA;
107  }
108 
109  w = xmax - xmin + 1;
110  h = ymax - ymin + 1;
111 
112  bytestream2_skipu(&gb, 49);
113  nplanes = bytestream2_get_byteu(&gb);
114  bytes_per_line = bytestream2_get_le16u(&gb);
115  bytes_per_scanline = nplanes * bytes_per_line;
116 
117  if (bytes_per_scanline < (w * bits_per_pixel * nplanes + 7) / 8 ||
118  (!compressed && bytes_per_scanline > bytestream2_get_bytes_left(&gb) / h)) {
119  av_log(avctx, AV_LOG_ERROR, "PCX data is corrupted\n");
120  return AVERROR_INVALIDDATA;
121  }
122 
123  switch ((nplanes << 8) + bits_per_pixel) {
124  case 0x0308:
125  avctx->pix_fmt = AV_PIX_FMT_RGB24;
126  break;
127  case 0x0108:
128  case 0x0104:
129  case 0x0102:
130  case 0x0101:
131  case 0x0401:
132  case 0x0301:
133  case 0x0201:
134  avctx->pix_fmt = AV_PIX_FMT_PAL8;
135  break;
136  default:
137  av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n");
138  return AVERROR_INVALIDDATA;
139  }
140 
141  bytestream2_skipu(&gb, 60);
142 
143  if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
144  return ret;
145 
146  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
147  return ret;
148 
150 
151  ptr = p->data[0];
152  stride = p->linesize[0];
153 
154  scanline = av_malloc(bytes_per_scanline + AV_INPUT_BUFFER_PADDING_SIZE);
155  if (!scanline)
156  return AVERROR(ENOMEM);
157 
158  if (nplanes == 3 && bits_per_pixel == 8) {
159  for (y = 0; y < h; y++) {
160  ret = pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
161  if (ret < 0)
162  goto end;
163 
164  for (x = 0; x < w; x++) {
165  ptr[3 * x] = scanline[x];
166  ptr[3 * x + 1] = scanline[x + bytes_per_line];
167  ptr[3 * x + 2] = scanline[x + (bytes_per_line << 1)];
168  }
169 
170  ptr += stride;
171  }
172  } else if (nplanes == 1 && bits_per_pixel == 8) {
173  int palstart = avpkt->size - 769;
174 
175  if (avpkt->size < 769) {
176  av_log(avctx, AV_LOG_ERROR, "File is too short\n");
177  ret = avctx->err_recognition & AV_EF_EXPLODE ?
178  AVERROR_INVALIDDATA : avpkt->size;
179  goto end;
180  }
181 
182  for (y = 0; y < h; y++, ptr += stride) {
183  ret = pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
184  if (ret < 0)
185  goto end;
186  memcpy(ptr, scanline, w);
187  }
188 
189  if (bytestream2_tell(&gb) != palstart) {
190  av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n");
191  bytestream2_seek(&gb, palstart, SEEK_SET);
192  }
193  if (bytestream2_get_byte(&gb) != 12) {
194  av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
195  ret = avctx->err_recognition & AV_EF_EXPLODE ?
196  AVERROR_INVALIDDATA : avpkt->size;
197  goto end;
198  }
199  } else if (nplanes == 1) { /* all packed formats, max. 16 colors */
201 
202  for (y = 0; y < h; y++) {
203  init_get_bits8(&s, scanline, bytes_per_scanline);
204 
205  ret = pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
206  if (ret < 0)
207  goto end;
208 
209  for (x = 0; x < w; x++)
210  ptr[x] = get_bits(&s, bits_per_pixel);
211  ptr += stride;
212  }
213  } else { /* planar, 4, 8 or 16 colors */
214  int i;
215 
216  for (y = 0; y < h; y++) {
217  ret = pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
218  if (ret < 0)
219  goto end;
220 
221  for (x = 0; x < w; x++) {
222  int m = 0x80 >> (x & 7), v = 0;
223  for (i = nplanes - 1; i >= 0; i--) {
224  v <<= 1;
225  v += !!(scanline[i * bytes_per_line + (x >> 3)] & m);
226  }
227  ptr[x] = v;
228  }
229  ptr += stride;
230  }
231  }
232 
233  ret = bytestream2_tell(&gb);
234  if (nplanes == 1 && bits_per_pixel == 8) {
235  pcx_palette(&gb, (uint32_t *)p->data[1], 256);
236  ret += 256 * 3;
237  } else if (bits_per_pixel * nplanes == 1) {
238  AV_WN32A(p->data[1] , 0xFF000000);
239  AV_WN32A(p->data[1]+4, 0xFFFFFFFF);
240  } else if (bits_per_pixel < 8) {
241  bytestream2_seek(&gb, 16, SEEK_SET);
242  pcx_palette(&gb, (uint32_t *)p->data[1], 16);
243  }
244 
245  *got_frame = 1;
246 
247 end:
248  av_free(scanline);
249  return ret;
250 }
251 
253  .name = "pcx",
254  .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
255  .type = AVMEDIA_TYPE_VIDEO,
256  .id = AV_CODEC_ID_PCX,
257  .decode = pcx_decode_frame,
258  .capabilities = AV_CODEC_CAP_DR1,
259 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
misc image utilities
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:381
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:68
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:104
int num
Numerator.
Definition: rational.h:59
int size
Definition: avcodec.h:1445
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel...
Definition: avcodec.h:1911
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1742
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
AVCodec ff_pcx_decoder
Definition: pcx.c:252
uint8_t run
Definition: svq3.c:206
AVCodec.
Definition: avcodec.h:3423
#define AV_WN32A(p, v)
Definition: intreadwrite.h:538
uint8_t
#define av_malloc(s)
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
#define PCX_HEADER_SIZE
Definition: pcx.c:31
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
uint8_t * data
Definition: avcodec.h:1444
static av_always_inline void bytestream2_skipu(GetByteContext *g, unsigned int size)
Definition: bytestream.h:170
bitstream reader API header.
static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: pcx.c:72
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:263
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
const char * name
Name of the codec implementation.
Definition: avcodec.h:3430
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:301
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2657
#define FFMIN(a, b)
Definition: common.h:96
static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
Definition: pcx.c:61
uint8_t w
Definition: llviddspenc.c:38
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
#define s(width, name)
Definition: cbs_vp9.c:257
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:2668
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:188
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:249
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:650
main external API structure.
Definition: avcodec.h:1532
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1922
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:232
common internal api header.
int den
Denominator.
Definition: rational.h:60
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:781
static int pcx_rle_decode(GetByteContext *gb, uint8_t *dst, unsigned int bytes_per_scanline, int compressed)
Definition: pcx.c:33
#define av_free(p)
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:208
#define stride
This structure stores compressed data.
Definition: avcodec.h:1421
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:967