Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / aliaspixdec.c
1 /*
2 * Alias PIX image decoder
3 * Copyright (C) 2014 Vittorio Giovara <vittorio.giovara@gmail.com>
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 "libavutil/intreadwrite.h"
23
24 #include "avcodec.h"
25 #include "bytestream.h"
26 #include "internal.h"
27
28 #define ALIAS_HEADER_SIZE 10
29
30 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
31 AVPacket *avpkt)
32 {
33 AVFrame *f = data;
34 GetByteContext gb;
35 int width, height, ret, bits_pixel, pixel;
36 uint8_t *out_buf;
37 uint8_t count;
38 int x, y;
39
40 bytestream2_init(&gb, avpkt->data, avpkt->size);
41
42 if (bytestream2_get_bytes_left(&gb) < ALIAS_HEADER_SIZE) {
43 av_log(avctx, AV_LOG_ERROR, "Header too small %d.\n", avpkt->size);
44 return AVERROR_INVALIDDATA;
45 }
46
47 width = bytestream2_get_be16u(&gb);
48 height = bytestream2_get_be16u(&gb);
49 bytestream2_skipu(&gb, 4); // obsolete X, Y offset
50 bits_pixel = bytestream2_get_be16u(&gb);
51
52 if (bits_pixel == 24)
53 avctx->pix_fmt = AV_PIX_FMT_BGR24;
54 else if (bits_pixel == 8)
55 avctx->pix_fmt = AV_PIX_FMT_GRAY8;
56 else {
57 av_log(avctx, AV_LOG_ERROR, "Invalid pixel format.\n");
58 return AVERROR_INVALIDDATA;
59 }
60
61 ret = ff_set_dimensions(avctx, width, height);
62 if (ret < 0)
63 return ret;
64
65 ret = ff_get_buffer(avctx, f, 0);
66 if (ret < 0)
67 return ret;
68
69 f->pict_type = AV_PICTURE_TYPE_I;
70 f->key_frame = 1;
71
72 x = 0;
73 y = 1;
74 out_buf = f->data[0];
75 while (bytestream2_get_bytes_left(&gb) > 0) {
76 int i;
77
78 /* set buffer at the right position at every new line */
79 if (x == avctx->width) {
80 x = 0;
81 out_buf = f->data[0] + f->linesize[0] * y++;
82 if (y > avctx->height) {
83 av_log(avctx, AV_LOG_ERROR,
84 "Ended frame decoding with %d bytes left.\n",
85 bytestream2_get_bytes_left(&gb));
86 return AVERROR_INVALIDDATA;
87 }
88 }
89
90 /* read packet and copy data */
91 count = bytestream2_get_byteu(&gb);
92 if (!count || x + count > avctx->width) {
93 av_log(avctx, AV_LOG_ERROR, "Invalid run length %d.\n", count);
94 return AVERROR_INVALIDDATA;
95 }
96
97 if (avctx->pix_fmt == AV_PIX_FMT_BGR24) {
98 pixel = bytestream2_get_be24(&gb);
99 for (i = 0; i < count; i++) {
100 AV_WB24(out_buf, pixel);
101 out_buf += 3;
102 }
103 } else { // AV_PIX_FMT_GRAY8
104 pixel = bytestream2_get_byte(&gb);
105 for (i = 0; i < count; i++)
106 *out_buf++ = pixel;
107 }
108
109 x += i;
110 }
111
112 if (x != width || y != height) {
113 av_log(avctx, AV_LOG_ERROR, "Picture stopped at %d,%d.\n", x, y);
114 return AVERROR_INVALIDDATA;
115 }
116
117 *got_frame = 1;
118 return avpkt->size;
119 }
120
121 AVCodec ff_alias_pix_decoder = {
122 .name = "alias_pix",
123 .long_name = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"),
124 .type = AVMEDIA_TYPE_VIDEO,
125 .id = AV_CODEC_ID_ALIAS_PIX,
126 .decode = decode_frame,
127 .capabilities = CODEC_CAP_DR1,
128 };