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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 (compressed) {
42  while (i < bytes_per_scanline && bytestream2_get_bytes_left(gb)>0) {
43  run = 1;
44  value = bytestream2_get_byte(gb);
45  if (value >= 0xc0 && bytestream2_get_bytes_left(gb)>0) {
46  run = value & 0x3f;
47  value = bytestream2_get_byte(gb);
48  }
49  while (i < bytes_per_scanline && run--)
50  dst[i++] = value;
51  }
52  } else {
53  bytestream2_get_buffer(gb, dst, bytes_per_scanline);
54  }
55 }
56 
57 static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
58 {
59  int i;
60 
61  pallen = FFMIN(pallen, bytestream2_get_bytes_left(gb) / 3);
62  for (i = 0; i < pallen; i++)
63  *dst++ = 0xFF000000 | bytestream2_get_be24u(gb);
64  if (pallen < 256)
65  memset(dst, 0, (256 - pallen) * sizeof(*dst));
66 }
67 
68 static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
69  AVPacket *avpkt)
70 {
71  GetByteContext gb;
72  AVFrame * const p = data;
73  int compressed, xmin, ymin, xmax, ymax;
74  int ret;
75  unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x,
76  bytes_per_scanline;
77  uint8_t *ptr, *scanline;
78 
79  if (avpkt->size < PCX_HEADER_SIZE) {
80  av_log(avctx, AV_LOG_ERROR, "Packet too small\n");
81  return AVERROR_INVALIDDATA;
82  }
83 
84  bytestream2_init(&gb, avpkt->data, avpkt->size);
85 
86  if (bytestream2_get_byteu(&gb) != 0x0a || bytestream2_get_byteu(&gb) > 5) {
87  av_log(avctx, AV_LOG_ERROR, "this is not PCX encoded data\n");
88  return AVERROR_INVALIDDATA;
89  }
90 
91  compressed = bytestream2_get_byteu(&gb);
92  bits_per_pixel = bytestream2_get_byteu(&gb);
93  xmin = bytestream2_get_le16u(&gb);
94  ymin = bytestream2_get_le16u(&gb);
95  xmax = bytestream2_get_le16u(&gb);
96  ymax = bytestream2_get_le16u(&gb);
97  avctx->sample_aspect_ratio.num = bytestream2_get_le16u(&gb);
98  avctx->sample_aspect_ratio.den = bytestream2_get_le16u(&gb);
99 
100  if (xmax < xmin || ymax < ymin) {
101  av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n");
102  return AVERROR_INVALIDDATA;
103  }
104 
105  w = xmax - xmin + 1;
106  h = ymax - ymin + 1;
107 
108  bytestream2_skipu(&gb, 49);
109  nplanes = bytestream2_get_byteu(&gb);
110  bytes_per_line = bytestream2_get_le16u(&gb);
111  bytes_per_scanline = nplanes * bytes_per_line;
112 
113  if (bytes_per_scanline < (w * bits_per_pixel * nplanes + 7) / 8 ||
114  (!compressed && bytes_per_scanline > bytestream2_get_bytes_left(&gb) / h)) {
115  av_log(avctx, AV_LOG_ERROR, "PCX data is corrupted\n");
116  return AVERROR_INVALIDDATA;
117  }
118 
119  switch ((nplanes << 8) + bits_per_pixel) {
120  case 0x0308:
121  avctx->pix_fmt = AV_PIX_FMT_RGB24;
122  break;
123  case 0x0108:
124  case 0x0104:
125  case 0x0102:
126  case 0x0101:
127  case 0x0401:
128  case 0x0301:
129  case 0x0201:
130  avctx->pix_fmt = AV_PIX_FMT_PAL8;
131  break;
132  default:
133  av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n");
134  return AVERROR_INVALIDDATA;
135  }
136 
137  bytestream2_skipu(&gb, 60);
138 
139  if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
140  return ret;
141 
142  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
143  return ret;
144 
146 
147  ptr = p->data[0];
148  stride = p->linesize[0];
149 
150  scanline = av_malloc(bytes_per_scanline + AV_INPUT_BUFFER_PADDING_SIZE);
151  if (!scanline)
152  return AVERROR(ENOMEM);
153 
154  if (nplanes == 3 && bits_per_pixel == 8) {
155  for (y = 0; y < h; y++) {
156  pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
157 
158  for (x = 0; x < w; x++) {
159  ptr[3 * x] = scanline[x];
160  ptr[3 * x + 1] = scanline[x + bytes_per_line];
161  ptr[3 * x + 2] = scanline[x + (bytes_per_line << 1)];
162  }
163 
164  ptr += stride;
165  }
166  } else if (nplanes == 1 && bits_per_pixel == 8) {
167  int palstart = avpkt->size - 769;
168 
169  if (avpkt->size < 769) {
170  av_log(avctx, AV_LOG_ERROR, "File is too short\n");
171  ret = avctx->err_recognition & AV_EF_EXPLODE ?
172  AVERROR_INVALIDDATA : avpkt->size;
173  goto end;
174  }
175 
176  for (y = 0; y < h; y++, ptr += stride) {
177  pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
178  memcpy(ptr, scanline, w);
179  }
180 
181  if (bytestream2_tell(&gb) != palstart) {
182  av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n");
183  bytestream2_seek(&gb, palstart, SEEK_SET);
184  }
185  if (bytestream2_get_byte(&gb) != 12) {
186  av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
187  ret = avctx->err_recognition & AV_EF_EXPLODE ?
188  AVERROR_INVALIDDATA : avpkt->size;
189  goto end;
190  }
191  } else if (nplanes == 1) { /* all packed formats, max. 16 colors */
193 
194  for (y = 0; y < h; y++) {
195  init_get_bits8(&s, scanline, bytes_per_scanline);
196 
197  pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
198 
199  for (x = 0; x < w; x++)
200  ptr[x] = get_bits(&s, bits_per_pixel);
201  ptr += stride;
202  }
203  } else { /* planar, 4, 8 or 16 colors */
204  int i;
205 
206  for (y = 0; y < h; y++) {
207  pcx_rle_decode(&gb, scanline, bytes_per_scanline, compressed);
208 
209  for (x = 0; x < w; x++) {
210  int m = 0x80 >> (x & 7), v = 0;
211  for (i = nplanes - 1; i >= 0; i--) {
212  v <<= 1;
213  v += !!(scanline[i * bytes_per_line + (x >> 3)] & m);
214  }
215  ptr[x] = v;
216  }
217  ptr += stride;
218  }
219  }
220 
221  ret = bytestream2_tell(&gb);
222  if (nplanes == 1 && bits_per_pixel == 8) {
223  pcx_palette(&gb, (uint32_t *)p->data[1], 256);
224  ret += 256 * 3;
225  } else if (bits_per_pixel * nplanes == 1) {
226  AV_WN32A(p->data[1] , 0xFF000000);
227  AV_WN32A(p->data[1]+4, 0xFFFFFFFF);
228  } else if (bits_per_pixel < 8) {
229  bytestream2_seek(&gb, 16, SEEK_SET);
230  pcx_palette(&gb, (uint32_t *)p->data[1], 16);
231  }
232 
233  *got_frame = 1;
234 
235 end:
236  av_free(scanline);
237  return ret;
238 }
239 
241  .name = "pcx",
242  .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
243  .type = AVMEDIA_TYPE_VIDEO,
244  .id = AV_CODEC_ID_PCX,
245  .decode = pcx_decode_frame,
246  .capabilities = AV_CODEC_CAP_DR1,
247 };
const char * s
Definition: avisynth_c.h:768
#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:201
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:261
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:64
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:196
int num
Numerator.
Definition: rational.h:59
int size
Definition: avcodec.h:1415
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:1880
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1711
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:240
uint8_t run
Definition: svq3.c:206
AVCodec.
Definition: avcodec.h:3365
#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:73
#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:1414
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:68
#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:3372
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:284
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2626
#define FFMIN(a, b)
Definition: common.h:96
static void pcx_palette(GetByteContext *gb, uint32_t *dst, int pallen)
Definition: pcx.c:57
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:2637
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:232
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:456
main external API structure.
Definition: avcodec.h:1502
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1886
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:215
static void pcx_rle_decode(GetByteContext *gb, uint8_t *dst, unsigned int bytes_per_scanline, int compressed)
Definition: pcx.c:33
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:770
#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:1391
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:956