1 /*
2 * Alias PIX image encoder
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
encode_frame(AVCodecContext * avctx,AVPacket * pkt,const AVFrame * frame,int * got_packet)30 static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
31 const AVFrame *frame, int *got_packet)
32 {
33 int width, height, bits_pixel, i, j, length, ret;
34 uint8_t *in_buf, *buf;
35
36 #if FF_API_CODED_FRAME
37 FF_DISABLE_DEPRECATION_WARNINGS
38 avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
39 avctx->coded_frame->key_frame = 1;
40 FF_ENABLE_DEPRECATION_WARNINGS
41 #endif
42
43 width = avctx->width;
44 height = avctx->height;
45
46 if (width > 65535 || height > 65535 ||
47 width * height >= INT_MAX / 4 - ALIAS_HEADER_SIZE) {
48 av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n", width, height);
49 return AVERROR_INVALIDDATA;
50 }
51
52 switch (avctx->pix_fmt) {
53 case AV_PIX_FMT_GRAY8:
54 bits_pixel = 8;
55 break;
56 case AV_PIX_FMT_BGR24:
57 bits_pixel = 24;
58 break;
59 default:
60 return AVERROR(EINVAL);
61 }
62
63 length = ALIAS_HEADER_SIZE + 4 * width * height; // max possible
64 if ((ret = ff_alloc_packet2(avctx, pkt, length, ALIAS_HEADER_SIZE + height*2)) < 0) {
65 av_log(avctx, AV_LOG_ERROR, "Error getting output packet of size %d.\n", length);
66 return ret;
67 }
68
69 buf = pkt->data;
70
71 /* Encode header. */
72 bytestream_put_be16(&buf, width);
73 bytestream_put_be16(&buf, height);
74 bytestream_put_be32(&buf, 0); /* X, Y offset */
75 bytestream_put_be16(&buf, bits_pixel);
76
77 for (j = 0; j < height; j++) {
78 in_buf = frame->data[0] + frame->linesize[0] * j;
79 for (i = 0; i < width; ) {
80 int count = 0;
81 int pixel;
82
83 if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
84 pixel = *in_buf;
85 while (count < 255 && count + i < width && pixel == *in_buf) {
86 count++;
87 in_buf++;
88 }
89 bytestream_put_byte(&buf, count);
90 bytestream_put_byte(&buf, pixel);
91 } else { /* AV_PIX_FMT_BGR24 */
92 pixel = AV_RB24(in_buf);
93 while (count < 255 && count + i < width &&
94 pixel == AV_RB24(in_buf)) {
95 count++;
96 in_buf += 3;
97 }
98 bytestream_put_byte(&buf, count);
99 bytestream_put_be24(&buf, pixel);
100 }
101 i += count;
102 }
103 }
104
105 /* Total length */
106 av_shrink_packet(pkt, buf - pkt->data);
107 pkt->flags |= AV_PKT_FLAG_KEY;
108 *got_packet = 1;
109
110 return 0;
111 }
112
113 AVCodec ff_alias_pix_encoder = {
114 .name = "alias_pix",
115 .long_name = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"),
116 .type = AVMEDIA_TYPE_VIDEO,
117 .id = AV_CODEC_ID_ALIAS_PIX,
118 .encode2 = encode_frame,
119 .pix_fmts = (const enum AVPixelFormat[]) {
120 AV_PIX_FMT_BGR24, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE
121 },
122 };
123