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
pgx_get_number(AVCodecContext * avctx,GetByteContext * g,int * number)27 static int pgx_get_number(AVCodecContext *avctx, GetByteContext *g, int *number) {
28 int ret = AVERROR_INVALIDDATA;
29 char digit;
30
31 *number = 0;
32 while (1) {
33 uint64_t temp;
34 if (!bytestream2_get_bytes_left(g))
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
pgx_decode_header(AVCodecContext * avctx,GetByteContext * g,int * depth,int * width,int * height,int * sign)52 static int pgx_decode_header(AVCodecContext *avctx, GetByteContext *g,
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(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
pgx_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)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;
127 GetByteContext g;
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;
150 p->pict_type = AV_PICTURE_TYPE_I;
151 p->key_frame = 1;
152 avctx->bits_per_raw_sample = depth;
153 if (bpp == 8)
154 write_frame_8(p, &g, width, height, sign, depth);
155 else if (bpp == 16)
156 write_frame_16(p, &g, width, height, sign, depth);
157 *got_frame = 1;
158 return 0;
159 }
160
161 AVCodec ff_pgx_decoder = {
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 };
169