FFmpeg
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:268
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
misc image utilities
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
#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:1478
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:1944
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
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:3477
#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
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
uint8_t * data
Definition: avcodec.h:1477
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 i(width, name, range_min, range_max)
Definition: cbs_h2645.c:260
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#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:3484
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:351
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2690
#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
#define s(width, name)
Definition: cbs_vp9.c:257
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:2701
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:299
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:677
main external API structure.
Definition: avcodec.h:1565
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1964
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:282
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:790
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
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
Definition: avcodec.h:1454
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981