FFmpeg
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://bespin.org/~qz/pc-gpe/pcx.txt
27  */
28 
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "libavutil/imgutils.h"
32 #include "encode.h"
33 #include "internal.h"
34 
35 static const uint32_t monoblack_pal[16] = { 0x000000, 0xFFFFFF };
36 
37 /**
38  * PCX run-length encoder
39  * @param dst output buffer
40  * @param dst_size size of output buffer
41  * @param src input buffer
42  * @param src_plane_size size of one plane of input buffer in bytes
43  * @param nplanes number of planes in input buffer
44  * @return number of bytes written to dst or -1 on error
45  * @bug will not work for nplanes != 1 && bpp != 8
46  */
47 static int pcx_rle_encode( uint8_t *dst, int dst_size,
48  const uint8_t *src, int src_plane_size, int nplanes)
49 {
50  int p;
51  const uint8_t *dst_start = dst;
52 
53  // check worst-case upper bound on dst_size
54  if (dst_size < 2LL * src_plane_size * nplanes || src_plane_size <= 0)
55  return AVERROR(EINVAL);
56 
57  for (p = 0; p < nplanes; p++) {
58  int count = 1;
59  const uint8_t *src_plane = src + p;
60  const uint8_t *src_plane_end = src_plane + src_plane_size * nplanes;
61  uint8_t prev = *src_plane;
62  src_plane += nplanes;
63 
64  for (; ; src_plane += nplanes) {
65  if (src_plane < src_plane_end && *src_plane == prev && count < 0x3F) {
66  // current byte is same as prev
67  ++count;
68  } else {
69  // output prev * count
70  if (count != 1 || prev >= 0xC0)
71  *dst++ = 0xC0 | count;
72  *dst++ = prev;
73 
74  if (src_plane == src_plane_end)
75  break;
76 
77  // start new run
78  count = 1;
79  prev = *src_plane;
80  }
81  }
82  }
83 
84  return dst - dst_start;
85 }
86 
88  const AVFrame *frame, int *got_packet)
89 {
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 
98  if (avctx->width > 65535 || avctx->height > 65535) {
99  av_log(avctx, AV_LOG_ERROR, "image dimensions do not fit in 16 bits\n");
100  return AVERROR(EINVAL);
101  }
102 
103  switch (avctx->pix_fmt) {
104  case AV_PIX_FMT_RGB24:
105  bpp = 8;
106  nplanes = 3;
107  break;
108  case AV_PIX_FMT_RGB8:
109  case AV_PIX_FMT_BGR8:
112  case AV_PIX_FMT_GRAY8:
113  bpp = 8;
114  nplanes = 1;
115  avpriv_set_systematic_pal2(palette256, avctx->pix_fmt);
116  pal = palette256;
117  break;
118  case AV_PIX_FMT_PAL8:
119  bpp = 8;
120  nplanes = 1;
121  pal = (uint32_t *)frame->data[1];
122  break;
124  bpp = 1;
125  nplanes = 1;
126  pal = monoblack_pal;
127  break;
128  default:
129  av_log(avctx, AV_LOG_ERROR, "unsupported pixfmt\n");
130  return AVERROR(EINVAL);
131  }
132 
133  line_bytes = (avctx->width * bpp + 7) >> 3;
134  line_bytes = (line_bytes + 1) & ~1;
135 
136  max_pkt_size = 128 + avctx->height * 2 * line_bytes * nplanes + (pal ? 256*3 + 1 : 0);
137  if ((ret = ff_alloc_packet(avctx, pkt, max_pkt_size)) < 0)
138  return ret;
139  buf = pkt->data;
140  buf_end = pkt->data + pkt->size;
141 
142  sw = avctx->sample_aspect_ratio.num;
143  sh = avctx->sample_aspect_ratio.den;
144  if (sw > 0xFFFFu || sh > 0xFFFFu)
145  av_reduce(&sw, &sh, sw, sh, 0xFFFFu);
146 
147  bytestream_put_byte(&buf, 10); // manufacturer
148  bytestream_put_byte(&buf, 5); // version
149  bytestream_put_byte(&buf, 1); // encoding
150  bytestream_put_byte(&buf, bpp); // bits per pixel per plane
151  bytestream_put_le16(&buf, 0); // x min
152  bytestream_put_le16(&buf, 0); // y min
153  bytestream_put_le16(&buf, avctx->width - 1); // x max
154  bytestream_put_le16(&buf, avctx->height - 1); // y max
155  bytestream_put_le16(&buf, sw); // horizontal DPI
156  bytestream_put_le16(&buf, sh); // vertical DPI
157  for (i = 0; i < 16; i++)
158  bytestream_put_be24(&buf, pal ? pal[i] : 0);// palette (<= 16 color only)
159  bytestream_put_byte(&buf, 0); // reserved
160  bytestream_put_byte(&buf, nplanes); // number of planes
161  bytestream_put_le16(&buf, line_bytes); // scanline plane size in bytes
162 
163  while (buf - pkt->data < 128)
164  *buf++= 0;
165 
166  src = frame->data[0];
167 
168  for (y = 0; y < avctx->height; y++) {
169  if ((written = pcx_rle_encode(buf, buf_end - buf,
170  src, line_bytes, nplanes)) < 0) {
171  av_log(avctx, AV_LOG_ERROR, "buffer too small\n");
172  return AVERROR_BUG;
173  }
174  buf += written;
175  src += frame->linesize[0];
176  }
177 
178  if (nplanes == 1 && bpp == 8) {
179  if (buf_end - buf < 257) {
180  av_log(avctx, AV_LOG_ERROR, "buffer too small\n");
181  return AVERROR_BUG;
182  }
183  bytestream_put_byte(&buf, 12);
184  for (i = 0; i < 256; i++) {
185  bytestream_put_be24(&buf, pal[i]);
186  }
187  }
188 
189  pkt->size = buf - pkt->data;
190  *got_packet = 1;
191 
192  return 0;
193 }
194 
196  .name = "pcx",
197  .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
198  .type = AVMEDIA_TYPE_VIDEO,
199  .id = AV_CODEC_ID_PCX,
200  .encode2 = pcx_encode_frame,
201  .pix_fmts = (const enum AVPixelFormat[]){
207  },
208  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
209 };
AVCodec
AVCodec.
Definition: codec.h:202
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:42
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVERROR
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
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:373
encode.h
av_reduce
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
AVRational::num
int num
Numerator.
Definition: rational.h:59
AV_PIX_FMT_BGR8
@ AV_PIX_FMT_BGR8
packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
Definition: pixfmt.h:83
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
avpriv_set_systematic_pal2
int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt)
Definition: imgutils.c:178
NULL
#define NULL
Definition: coverity.c:32
monoblack_pal
static const uint32_t monoblack_pal[16]
Definition: pcxenc.c:35
AV_PIX_FMT_MONOBLACK
@ AV_PIX_FMT_MONOBLACK
Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb.
Definition: pixfmt.h:76
src
#define src
Definition: vp8dsp.c:255
AV_PIX_FMT_RGB8
@ AV_PIX_FMT_RGB8
packed RGB 3:3:2, 8bpp, (msb)2R 3G 3B(lsb)
Definition: pixfmt.h:86
AV_PIX_FMT_GRAY8
@ AV_PIX_FMT_GRAY8
Y , 8bpp.
Definition: pixfmt.h:74
AV_PIX_FMT_BGR4_BYTE
@ AV_PIX_FMT_BGR4_BYTE
packed RGB 1:2:1, 8bpp, (msb)1B 2G 1R(lsb)
Definition: pixfmt.h:85
ff_pcx_encoder
const AVCodec ff_pcx_encoder
Definition: pcxenc.c:195
AV_PIX_FMT_RGB24
@ AV_PIX_FMT_RGB24
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:68
AVPacket::size
int size
Definition: packet.h:374
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AV_CODEC_ID_PCX
@ AV_CODEC_ID_PCX
Definition: codec_id.h:159
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
AV_PIX_FMT_RGB4_BYTE
@ AV_PIX_FMT_RGB4_BYTE
packed RGB 1:2:1, 8bpp, (msb)1R 2G 1B(lsb)
Definition: pixfmt.h:88
AVCodecContext::height
int height
Definition: avcodec.h:556
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:593
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AVCodecContext
main external API structure.
Definition: avcodec.h:383
AVRational::den
int den
Denominator.
Definition: rational.h:60
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
pcx_rle_encode
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:47
pcx_encode_frame
static int pcx_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
Definition: pcxenc.c:87
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:556
bytestream.h
imgutils.h
AVERROR_BUG
#define AVERROR_BUG
Internal bug, also see AVERROR_BUG2.
Definition: error.h:52
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
ff_alloc_packet
int ff_alloc_packet(AVCodecContext *avctx, AVPacket *avpkt, int64_t size)
Check AVPacket size and allocate data.
Definition: encode.c:34
AVCodecContext::sample_aspect_ratio
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:753