Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "internal.h"
32 
33 static const uint32_t monoblack_pal[16] = { 0x000000, 0xFFFFFF };
34 
36 {
37 #if FF_API_CODED_FRAME
40  avctx->coded_frame->key_frame = 1;
42 #endif
43 
44  return 0;
45 }
46 
57 static int pcx_rle_encode( uint8_t *dst, int dst_size,
58  const uint8_t *src, int src_plane_size, int nplanes)
59 {
60  int p;
61  const uint8_t *dst_start = dst;
62 
63  // check worst-case upper bound on dst_size
64  if (dst_size < 2LL * src_plane_size * nplanes || src_plane_size <= 0)
65  return AVERROR(EINVAL);
66 
67  for (p = 0; p < nplanes; p++) {
68  int count = 1;
69  const uint8_t *src_plane = src + p;
70  const uint8_t *src_plane_end = src_plane + src_plane_size * nplanes;
71  uint8_t prev = *src_plane;
72  src_plane += nplanes;
73 
74  for (; ; src_plane += nplanes) {
75  if (src_plane < src_plane_end && *src_plane == prev && count < 0x3F) {
76  // current byte is same as prev
77  ++count;
78  } else {
79  // output prev * count
80  if (count != 1 || prev >= 0xC0)
81  *dst++ = 0xC0 | count;
82  *dst++ = prev;
83 
84  if (src_plane == src_plane_end)
85  break;
86 
87  // start new run
88  count = 1;
89  prev = *src_plane;
90  }
91  }
92  }
93 
94  return dst - dst_start;
95 }
96 
97 static int pcx_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
98  const AVFrame *frame, int *got_packet)
99 {
100  const uint8_t *buf_end;
101  uint8_t *buf;
102 
103  int bpp, nplanes, i, y, line_bytes, written, ret, max_pkt_size;
104  const uint32_t *pal = NULL;
105  const uint8_t *src;
106 
107  if (avctx->width > 65535 || avctx->height > 65535) {
108  av_log(avctx, AV_LOG_ERROR, "image dimensions do not fit in 16 bits\n");
109  return AVERROR(EINVAL);
110  }
111 
112  switch (avctx->pix_fmt) {
113  case AV_PIX_FMT_RGB24:
114  bpp = 8;
115  nplanes = 3;
116  break;
117  case AV_PIX_FMT_RGB8:
118  case AV_PIX_FMT_BGR8:
121  case AV_PIX_FMT_GRAY8:
122  case AV_PIX_FMT_PAL8:
123  bpp = 8;
124  nplanes = 1;
125  pal = (uint32_t *)frame->data[1];
126  break;
128  bpp = 1;
129  nplanes = 1;
130  pal = monoblack_pal;
131  break;
132  default:
133  av_log(avctx, AV_LOG_ERROR, "unsupported pixfmt\n");
134  return AVERROR(EINVAL);
135  }
136 
137  line_bytes = (avctx->width * bpp + 7) >> 3;
138  line_bytes = (line_bytes + 1) & ~1;
139 
140  max_pkt_size = 128 + avctx->height * 2 * line_bytes * nplanes + (pal ? 256*3 + 1 : 0);
141  if ((ret = ff_alloc_packet(pkt, max_pkt_size)) < 0) {
142  av_log(avctx, AV_LOG_ERROR, "Error getting output packet of size %d.\n", max_pkt_size);
143  return ret;
144  }
145  buf = pkt->data;
146  buf_end = pkt->data + pkt->size;
147 
148  bytestream_put_byte(&buf, 10); // manufacturer
149  bytestream_put_byte(&buf, 5); // version
150  bytestream_put_byte(&buf, 1); // encoding
151  bytestream_put_byte(&buf, bpp); // bits per pixel per plane
152  bytestream_put_le16(&buf, 0); // x min
153  bytestream_put_le16(&buf, 0); // y min
154  bytestream_put_le16(&buf, avctx->width - 1); // x max
155  bytestream_put_le16(&buf, avctx->height - 1); // y max
156  bytestream_put_le16(&buf, 0); // horizontal DPI
157  bytestream_put_le16(&buf, 0); // vertical DPI
158  for (i = 0; i < 16; i++)
159  bytestream_put_be24(&buf, pal ? pal[i] : 0);// palette (<= 16 color only)
160  bytestream_put_byte(&buf, 0); // reserved
161  bytestream_put_byte(&buf, nplanes); // number of planes
162  bytestream_put_le16(&buf, line_bytes); // scanline plane size in bytes
163 
164  while (buf - pkt->data < 128)
165  *buf++= 0;
166 
167  src = frame->data[0];
168 
169  for (y = 0; y < avctx->height; y++) {
170  if ((written = pcx_rle_encode(buf, buf_end - buf,
171  src, line_bytes, nplanes)) < 0) {
172  av_log(avctx, AV_LOG_ERROR, "buffer too small\n");
173  return AVERROR_BUG;
174  }
175  buf += written;
176  src += frame->linesize[0];
177  }
178 
179  if (nplanes == 1 && bpp == 8) {
180  if (buf_end - buf < 257) {
181  av_log(avctx, AV_LOG_ERROR, "buffer too small\n");
182  return AVERROR_BUG;
183  }
184  bytestream_put_byte(&buf, 12);
185  for (i = 0; i < 256; i++) {
186  bytestream_put_be24(&buf, pal[i]);
187  }
188  }
189 
190  pkt->size = buf - pkt->data;
191  pkt->flags |= AV_PKT_FLAG_KEY;
192  *got_packet = 1;
193 
194  return 0;
195 }
196 
198  .name = "pcx",
199  .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
200  .type = AVMEDIA_TYPE_VIDEO,
201  .id = AV_CODEC_ID_PCX,
202  .init = pcx_encode_init,
203  .encode2 = pcx_encode_frame,
204  .pix_fmts = (const enum AVPixelFormat[]){
210  },
211 };
This structure describes decoded (raw) audio or video data.
Definition: frame.h:140
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:61
int size
Definition: avcodec.h:1347
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1621
AVCodec.
Definition: avcodec.h:3120
packed RGB 1:2:1, 8bpp, (msb)1B 2G 1R(lsb)
Definition: pixfmt.h:82
uint8_t
#define av_cold
Definition: attributes.h:66
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:70
uint8_t * data
Definition: avcodec.h:1346
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1378
#define src
Definition: vp8dsp.c:254
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
#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:148
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:57
const char * name
Name of the codec implementation.
Definition: avcodec.h:3127
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1352
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:201
packed RGB 1:2:1, 8bpp, (msb)1R 2G 1B(lsb)
Definition: pixfmt.h:85
int width
picture width / height.
Definition: avcodec.h:1580
static int pcx_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
Definition: pcxenc.c:97
int ff_alloc_packet(AVPacket *avpkt, int size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1211
NULL
Definition: eval.c:55
packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
Definition: pixfmt.h:80
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:158
main external API structure.
Definition: avcodec.h:1409
#define AVERROR_BUG
Bug detected, please report the issue.
Definition: error.h:60
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:146
Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb...
Definition: pixfmt.h:69
Y , 8bpp.
Definition: pixfmt.h:67
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:77
common internal api header.
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2797
packed RGB 3:3:2, 8bpp, (msb)2R 3G 3B(lsb)
Definition: pixfmt.h:83
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:78
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:196
static const uint32_t monoblack_pal[16]
Definition: pcxenc.c:33
static av_cold int pcx_encode_init(AVCodecContext *avctx)
Definition: pcxenc.c:35
AVPixelFormat
Pixel format.
Definition: pixfmt.h:57
This structure stores compressed data.
Definition: avcodec.h:1323
AVCodec ff_pcx_encoder
Definition: pcxenc.c:197