FFmpeg
pgxdec.c
Go to the documentation of this file.
1 /*
2  * PGX image format
3  * Copyright (c) 2020 Gautam Ramakrishnan
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 #include "avcodec.h"
23 #include "bytestream.h"
24 #include "codec_internal.h"
25 #include "decode.h"
26 
27 static int pgx_get_number(AVCodecContext *avctx, GetByteContext *g, int *number) {
29  char digit;
30 
31  *number = 0;
32  while (1) {
33  uint64_t temp;
34  if (bytestream2_get_bytes_left(g) <= 0)
35  return AVERROR_INVALIDDATA;
36  digit = bytestream2_get_byteu(g);
37  if (digit == ' ' || digit == 0xA || digit == 0xD)
38  break;
39  else if (digit < '0' || digit > '9')
40  return AVERROR_INVALIDDATA;
41 
42  temp = (uint64_t)10 * (*number) + (digit - '0');
43  if (temp > INT_MAX)
44  return AVERROR_INVALIDDATA;
45  *number = temp;
46  ret = 0;
47  }
48 
49  return ret;
50 }
51 
53  int *depth, int *width, int *height,
54  int *sign)
55 {
56  int byte;
57 
58  if (bytestream2_get_bytes_left(g) < 12)
59  return AVERROR_INVALIDDATA;
60 
61  bytestream2_skipu(g, 6);
62 
63  // Is the component signed?
64  byte = bytestream2_peek_byteu(g);
65  if (byte == '+') {
66  *sign = 0;
67  bytestream2_skipu(g, 1);
68  } else if (byte == '-') {
69  *sign = 1;
70  bytestream2_skipu(g, 1);
71  }
72 
73  byte = bytestream2_peek_byteu(g);
74  if (byte == ' ')
75  bytestream2_skipu(g, 1);
76 
77  if (pgx_get_number(avctx, g, depth))
78  goto error;
79  if (pgx_get_number(avctx, g, width))
80  goto error;
81  if (pgx_get_number(avctx, g, height))
82  goto error;
83 
84  if (bytestream2_peek_byte(g) == 0xA)
85  bytestream2_skip(g, 1);
86  return 0;
87 
88 error:
89  av_log(avctx, AV_LOG_ERROR, "Error in decoding header.\n");
90  return AVERROR_INVALIDDATA;
91 }
92 
93 #define WRITE_FRAME(D, PIXEL, suffix) \
94  static inline void write_frame_ ##D(AVFrame *frame, GetByteContext *g, \
95  int width, int height, int sign, int depth) \
96  { \
97  const unsigned offset = sign ? (1 << (D - 1)) : 0; \
98  int i, j; \
99  for (i = 0; i < height; i++) { \
100  PIXEL *line = (PIXEL*)(frame->data[0] + i * frame->linesize[0]); \
101  for (j = 0; j < width; j++) { \
102  unsigned val = bytestream2_get_ ##suffix##u(g) << (D - depth); \
103  val ^= offset; \
104  *(line + j) = val; \
105  } \
106  } \
107  } \
108 
109 WRITE_FRAME(8, uint8_t, byte)
110 WRITE_FRAME(16, uint16_t, be16)
111 
113  int *got_frame, AVPacket *avpkt)
114 {
115  int ret;
116  int bpp;
117  int width, height, depth;
118  int sign = 0;
120  bytestream2_init(&g, avpkt->data, avpkt->size);
121 
122  if ((ret = pgx_decode_header(avctx, &g, &depth, &width, &height, &sign)) < 0)
123  return ret;
124 
125  if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
126  return ret;
127 
128  if (depth > 0 && depth <= 8) {
129  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
130  bpp = 8;
131  } else if (depth > 0 && depth <= 16) {
132  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
133  bpp = 16;
134  } else {
135  av_log(avctx, AV_LOG_ERROR, "depth %d is invalid or unsupported.\n", depth);
136  return AVERROR_PATCHWELCOME;
137  }
138  if (bytestream2_get_bytes_left(&g) < width * height * (bpp >> 3))
139  return AVERROR_INVALIDDATA;
140  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
141  return ret;
142  p->pict_type = AV_PICTURE_TYPE_I;
143  p->key_frame = 1;
144  avctx->bits_per_raw_sample = depth;
145  if (bpp == 8)
146  write_frame_8(p, &g, width, height, sign, depth);
147  else if (bpp == 16)
148  write_frame_16(p, &g, width, height, sign, depth);
149  *got_frame = 1;
150  return 0;
151 }
152 
154  .p.name = "pgx",
155  CODEC_LONG_NAME("PGX (JPEG2000 Test Format)"),
156  .p.type = AVMEDIA_TYPE_VIDEO,
157  .p.id = AV_CODEC_ID_PGX,
158  .p.capabilities = AV_CODEC_CAP_DR1,
160 };
error
static void error(const char *err)
Definition: target_bsf_fuzzer.c:31
GetByteContext
Definition: bytestream.h:33
bytestream2_skipu
static av_always_inline void bytestream2_skipu(GetByteContext *g, unsigned int size)
Definition: bytestream.h:174
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
FFCodec
Definition: codec_internal.h:119
pgx_get_number
static int pgx_get_number(AVCodecContext *avctx, GetByteContext *g, int *number)
Definition: pgxdec.c:27
ff_set_dimensions
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:91
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:123
AV_PIX_FMT_GRAY16
#define AV_PIX_FMT_GRAY16
Definition: pixfmt.h:443
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
WRITE_FRAME
#define WRITE_FRAME(D, PIXEL, suffix)
Definition: pgxdec.c:93
width
#define width
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:298
g
const char * g
Definition: vf_curves.c:127
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:264
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
AV_PIX_FMT_GRAY8
@ AV_PIX_FMT_GRAY8
Y , 8bpp.
Definition: pixfmt.h:74
pgx_decode_header
static int pgx_decode_header(AVCodecContext *avctx, GetByteContext *g, int *depth, int *width, int *height, int *sign)
Definition: pgxdec.c:52
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1450
ff_pgx_decoder
const FFCodec ff_pgx_decoder
Definition: pgxdec.c:153
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
byte
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_WB16 unsigned int_TMPL byte
Definition: bytestream.h:99
codec_internal.h
height
#define height
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:211
avcodec.h
ret
ret
Definition: filter_design.txt:187
be16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL be16
Definition: bytestream.h:98
AVCodecContext
main external API structure.
Definition: avcodec.h:398
temp
else temp
Definition: vf_mcdeint.c:248
pgx_decode_frame
static int pgx_decode_frame(AVCodecContext *avctx, AVFrame *p, int *got_frame, AVPacket *avpkt)
Definition: pgxdec.c:112
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AV_CODEC_ID_PGX
@ AV_CODEC_ID_PGX
Definition: codec_id.h:247
AVPacket
This structure stores compressed data.
Definition: packet.h:351
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61