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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 
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 
142 
143  ptr = p->data[0];
144  stride = p->linesize[0];
145 
146  scanline = av_malloc(bytes_per_scanline + AV_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 */
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 
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 = AV_CODEC_CAP_DR1,
243 };
float v
const char * s
Definition: avisynth_c.h:631
#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:171
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:260
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:65
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:216
int num
numerator
Definition: rational.h:44
int size
Definition: avcodec.h:1423
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:1901
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1721
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:236
uint8_t run
Definition: svq3.c:149
AVCodec.
Definition: avcodec.h:3471
#define AV_WN32A(p, v)
Definition: intreadwrite.h:538
uint8_t
#define av_malloc(s)
8 bit with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:74
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
uint8_t * data
Definition: avcodec.h:1422
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:66
#define av_log(a,...)
unsigned m
Definition: audioconvert.c:187
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:2900
#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:175
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:3478
Libavcodec external API header.
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:242
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2889
#define FFMIN(a, b)
Definition: common.h:66
float y
static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
Definition: pcx.c:55
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:188
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:199
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:441
main external API structure.
Definition: avcodec.h:1501
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:1040
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:182
static void pcx_rle_decode(GetByteContext *gb, uint8_t *dst, unsigned int bytes_per_scanline, int compressed)
Definition: pcx.c:31
common internal api header.
int den
denominator
Definition: rational.h:45
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:635
#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:1399
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:856