path: root/libavcodec/aliaspixenc.c (plain)
blob: a9ba00cd29cc88a0e9538a320ddbcc3294bc3b43

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
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