FFmpeg
pgxdec.c
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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 "internal.h"
24 #include "bytestream.h"
25 #include "libavutil/imgutils.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;
35  return AVERROR_INVALIDDATA;
36  digit = bytestream2_get_byte(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) < 6) {
59  return AVERROR_INVALIDDATA;
60  }
61 
62  bytestream2_skip(g, 6);
63 
64  // Is the component signed?
65  byte = bytestream2_peek_byte(g);
66  if (byte == '+') {
67  *sign = 0;
68  bytestream2_skip(g, 1);
69  } else if (byte == '-') {
70  *sign = 1;
71  bytestream2_skip(g, 1);
72  } else if (byte == 0)
73  goto error;
74 
75  byte = bytestream2_peek_byte(g);
76  if (byte == ' ')
77  bytestream2_skip(g, 1);
78  else if (byte == 0)
79  goto error;
80 
81  if (pgx_get_number(avctx, g, depth))
82  goto error;
83  if (pgx_get_number(avctx, g, width))
84  goto error;
85  if (pgx_get_number(avctx, g, height))
86  goto error;
87 
88  if (bytestream2_peek_byte(g) == 0xA)
89  bytestream2_skip(g, 1);
90  return 0;
91 
92 error:
93  av_log(avctx, AV_LOG_ERROR, "Error in decoding header.\n");
94  return AVERROR_INVALIDDATA;
95 }
96 
97 #define WRITE_FRAME(D, PIXEL, suffix) \
98  static inline void write_frame_ ##D(AVPacket *avpkt, AVFrame *frame, GetByteContext *g, \
99  int width, int height, int sign, int depth) \
100  { \
101  int i, j; \
102  for (i = 0; i < height; i++) { \
103  PIXEL *line = (PIXEL*)frame->data[0] + i*frame->linesize[0]/sizeof(PIXEL); \
104  for (j = 0; j < width; j++) { \
105  unsigned val; \
106  if (sign) \
107  val = (PIXEL)bytestream2_get_ ##suffix(g) + (1 << (depth - 1)); \
108  else \
109  val = bytestream2_get_ ##suffix(g); \
110  val <<= (D - depth); \
111  *(line + j) = val; \
112  } \
113  } \
114  } \
115 
116 WRITE_FRAME(8, int8_t, byte)
117 WRITE_FRAME(16, int16_t, be16)
118 
119 static int pgx_decode_frame(AVCodecContext *avctx, void *data,
120  int *got_frame, AVPacket *avpkt)
121 {
122  AVFrame *p = data;
123  int ret;
124  int bpp;
125  int width, height, depth;
126  int sign = 0;
128  bytestream2_init(&g, avpkt->data, avpkt->size);
129 
130  if ((ret = pgx_decode_header(avctx, &g, &depth, &width, &height, &sign)) < 0)
131  return ret;
132 
133  if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
134  return ret;
135 
136  if (depth > 0 && depth <= 8) {
137  avctx->pix_fmt = AV_PIX_FMT_GRAY8;
138  bpp = 8;
139  } else if (depth > 0 && depth <= 16) {
140  avctx->pix_fmt = AV_PIX_FMT_GRAY16;
141  bpp = 16;
142  } else {
143  av_log(avctx, AV_LOG_ERROR, "depth %d is invalid or unsupported.\n", depth);
144  return AVERROR_PATCHWELCOME;
145  }
146  if (bytestream2_get_bytes_left(&g) < width * height * (bpp >> 3))
147  return AVERROR_INVALIDDATA;
148  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
149  return ret;
151  p->key_frame = 1;
152  avctx->bits_per_raw_sample = depth;
153  if (bpp == 8)
154  write_frame_8(avpkt, p, &g, width, height, sign, depth);
155  else if (bpp == 16)
156  write_frame_16(avpkt, p, &g, width, height, sign, depth);
157  *got_frame = 1;
158  return 0;
159 }
160 
162  .name = "pgx",
163  .long_name = NULL_IF_CONFIG_SMALL("PGX (JPEG2000 Test Format)"),
164  .type = AVMEDIA_TYPE_VIDEO,
165  .id = AV_CODEC_ID_PGX,
166  .decode = pgx_decode_frame,
167  .capabilities = AV_CODEC_CAP_DR1,
168 };
#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:308
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
misc image utilities
else temp
Definition: vf_mcdeint.c:256
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:106
const char * g
Definition: vf_curves.c:115
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
static int pgx_decode_header(AVCodecContext *avctx, GetByteContext *g, int *depth, int *width, int *height, int *sign)
Definition: pgxdec.c:52
static void error(const char *err)
AVCodec.
Definition: codec.h:190
#define height
#define av_log(a,...)
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
const char * name
Name of the codec implementation.
Definition: codec.h:197
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:91
#define WRITE_FRAME(D, PIXEL, suffix)
Definition: pgxdec.c:97
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:391
#define AV_PIX_FMT_GRAY16
Definition: pixfmt.h:383
#define width
AVCodec ff_pgx_decoder
Definition: pgxdec.c:161
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
Libavcodec external API header.
static int pgx_get_number(AVCodecContext *avctx, GetByteContext *g, int *number)
Definition: pgxdec.c:27
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:91
main external API structure.
Definition: avcodec.h:526
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1879
Y , 8bpp.
Definition: pixfmt.h:74
common internal api header.
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:386
static int pgx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: pgxdec.c:119
This structure stores compressed data.
Definition: packet.h:340
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:50