FFmpeg  2.1.1
pcxenc.c
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1 /*
2  * PC Paintbrush PCX (.pcx) image encoder
3  * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * PCX image encoder
25  * @author Daniel Verkamp
26  * @see http://www.qzx.com/pc-gpe/pcx.txt
27  */
28 
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "libavutil/imgutils.h"
32 #include "internal.h"
33 
34 static const uint32_t monoblack_pal[16] = { 0x000000, 0xFFFFFF };
35 
36 /**
37  * PCX run-length encoder
38  * @param dst output buffer
39  * @param dst_size size of output buffer
40  * @param src input buffer
41  * @param src_plane_size size of one plane of input buffer in bytes
42  * @param nplanes number of planes in input buffer
43  * @return number of bytes written to dst or -1 on error
44  * @bug will not work for nplanes != 1 && bpp != 8
45  */
46 static int pcx_rle_encode( uint8_t *dst, int dst_size,
47  const uint8_t *src, int src_plane_size, int nplanes)
48 {
49  int p;
50  const uint8_t *dst_start = dst;
51 
52  // check worst-case upper bound on dst_size
53  if (dst_size < 2LL * src_plane_size * nplanes || src_plane_size <= 0)
54  return -1;
55 
56  for (p = 0; p < nplanes; p++) {
57  int count = 1;
58  const uint8_t *src_plane = src + p;
59  const uint8_t *src_plane_end = src_plane + src_plane_size * nplanes;
60  uint8_t prev = *src_plane;
61  src_plane += nplanes;
62 
63  for (; ; src_plane += nplanes) {
64  if (src_plane < src_plane_end && *src_plane == prev && count < 0x3F) {
65  // current byte is same as prev
66  ++count;
67  } else {
68  // output prev * count
69  if (count != 1 || prev >= 0xC0)
70  *dst++ = 0xC0 | count;
71  *dst++ = prev;
72 
73  if (src_plane == src_plane_end)
74  break;
75 
76  // start new run
77  count = 1;
78  prev = *src_plane;
79  }
80  }
81  }
82 
83  return dst - dst_start;
84 }
85 
87  const AVFrame *frame, int *got_packet)
88 {
89  AVFrame *const pict = (AVFrame *) frame;
90  const uint8_t *buf_end;
91  uint8_t *buf;
92 
93  int bpp, nplanes, i, y, line_bytes, written, ret, max_pkt_size, sw, sh;
94  const uint32_t *pal = NULL;
95  uint32_t palette256[256];
96  const uint8_t *src;
97 
99  pict->key_frame = 1;
100 
101  if (avctx->width > 65535 || avctx->height > 65535) {
102  av_log(avctx, AV_LOG_ERROR, "image dimensions do not fit in 16 bits\n");
103  return -1;
104  }
105 
106  switch (avctx->pix_fmt) {
107  case AV_PIX_FMT_RGB24:
108  bpp = 8;
109  nplanes = 3;
110  break;
111  case AV_PIX_FMT_RGB8:
112  case AV_PIX_FMT_BGR8:
115  case AV_PIX_FMT_GRAY8:
116  bpp = 8;
117  nplanes = 1;
118  avpriv_set_systematic_pal2(palette256, avctx->pix_fmt);
119  pal = palette256;
120  break;
121  case AV_PIX_FMT_PAL8:
122  bpp = 8;
123  nplanes = 1;
124  pal = (uint32_t *)pict->data[1];
125  break;
127  bpp = 1;
128  nplanes = 1;
129  pal = monoblack_pal;
130  break;
131  default:
132  av_log(avctx, AV_LOG_ERROR, "unsupported pixfmt\n");
133  return -1;
134  }
135 
136  line_bytes = (avctx->width * bpp + 7) >> 3;
137  line_bytes = (line_bytes + 1) & ~1;
138 
139  max_pkt_size = 128 + avctx->height * 2 * line_bytes * nplanes + (pal ? 256*3 + 1 : 0);
140  if ((ret = ff_alloc_packet2(avctx, pkt, max_pkt_size)) < 0)
141  return ret;
142  buf = pkt->data;
143  buf_end = pkt->data + pkt->size;
144 
145  sw = avctx->sample_aspect_ratio.num;
146  sh = avctx->sample_aspect_ratio.den;
147  if (sw > 0xFFFFu || sh > 0xFFFFu)
148  av_reduce(&sw, &sh, sw, sh, 0xFFFFu);
149 
150  bytestream_put_byte(&buf, 10); // manufacturer
151  bytestream_put_byte(&buf, 5); // version
152  bytestream_put_byte(&buf, 1); // encoding
153  bytestream_put_byte(&buf, bpp); // bits per pixel per plane
154  bytestream_put_le16(&buf, 0); // x min
155  bytestream_put_le16(&buf, 0); // y min
156  bytestream_put_le16(&buf, avctx->width - 1); // x max
157  bytestream_put_le16(&buf, avctx->height - 1); // y max
158  bytestream_put_le16(&buf, sw); // horizontal DPI
159  bytestream_put_le16(&buf, sh); // vertical DPI
160  for (i = 0; i < 16; i++)
161  bytestream_put_be24(&buf, pal ? pal[i] : 0);// palette (<= 16 color only)
162  bytestream_put_byte(&buf, 0); // reserved
163  bytestream_put_byte(&buf, nplanes); // number of planes
164  bytestream_put_le16(&buf, line_bytes); // scanline plane size in bytes
165 
166  while (buf - pkt->data < 128)
167  *buf++= 0;
168 
169  src = pict->data[0];
170 
171  for (y = 0; y < avctx->height; y++) {
172  if ((written = pcx_rle_encode(buf, buf_end - buf,
173  src, line_bytes, nplanes)) < 0) {
174  av_log(avctx, AV_LOG_ERROR, "buffer too small\n");
175  return -1;
176  }
177  buf += written;
178  src += pict->linesize[0];
179  }
180 
181  if (nplanes == 1 && bpp == 8) {
182  if (buf_end - buf < 257) {
183  av_log(avctx, AV_LOG_ERROR, "buffer too small\n");
184  return -1;
185  }
186  bytestream_put_byte(&buf, 12);
187  for (i = 0; i < 256; i++) {
188  bytestream_put_be24(&buf, pal[i]);
189  }
190  }
191 
192  pkt->size = buf - pkt->data;
193  pkt->flags |= AV_PKT_FLAG_KEY;
194  *got_packet = 1;
195 
196  return 0;
197 }
198 
200  .name = "pcx",
201  .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
202  .type = AVMEDIA_TYPE_VIDEO,
203  .id = AV_CODEC_ID_PCX,
204  .encode2 = pcx_encode_frame,
205  .pix_fmts = (const enum AVPixelFormat[]){
211  },
212 };
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1500
This structure describes decoded (raw) audio or video data.
Definition: frame.h:96
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: avcodec.h:4536
int num
numerator
Definition: rational.h:44
int size
Definition: avcodec.h:1064
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:1517
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1342
packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
Definition: avcodec.h:4553
Pixel format.
Definition: avcodec.h:4533
AVCodec.
Definition: avcodec.h:2922
Y , 8bpp.
Definition: avcodec.h:4542
uint8_t
const char * name
Name of the codec implementation.
Definition: avcodec.h:2929
packed RGB 3:3:2, 8bpp, (msb)2R 3G 3B(lsb)
Definition: avcodec.h:4556
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1113
static AVFrame * frame
Definition: demuxing.c:51
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: avcodec.h:4147
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
static int pcx_rle_encode(uint8_t *dst, int dst_size, const uint8_t *src, int src_plane_size, int nplanes)
PCX run-length encoder.
Definition: pcxenc.c:46
int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt)
Definition: imgutils.c:150
Libavcodec external API header.
AVPixelFormat
Pixel format.
Definition: pixfmt.h:66
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1069
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:167
float y
ret
Definition: avfilter.c:961
int width
picture width / height.
Definition: avcodec.h:1314
static int pcx_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
Definition: pcxenc.c:86
packed RGB 1:2:1, 8bpp, (msb)1B 2G 1R(lsb)
Definition: avcodec.h:4555
AVS_Value src
Definition: avisynth_c.h:523
main external API structure.
Definition: avcodec.h:1146
void * buf
Definition: avisynth_c.h:594
uint8_t * data
Definition: avcodec.h:1063
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:124
common internal api header.
int den
denominator
Definition: rational.h:45
Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb...
Definition: avcodec.h:4544
int key_frame
1 -&gt; keyframe, 0-&gt; not
Definition: frame.h:162
static const uint32_t monoblack_pal[16]
Definition: pcxenc.c:34
void INT64 INT64 count
Definition: avisynth_c.h:594
static AVPacket pkt
Definition: demuxing.c:52
8 bit with PIX_FMT_RGB32 palette
Definition: avcodec.h:4545
packed RGB 1:2:1, 8bpp, (msb)1R 2G 1B(lsb)
Definition: avcodec.h:4558
This structure stores compressed data.
Definition: avcodec.h:1040
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:107
AVCodec ff_pcx_encoder
Definition: pcxenc.c:199