c6a9ba94a2d55f7fba64d8e80c859078c29f371a
[libav.git] / libavcodec / zerocodec.c
1 /*
2 * ZeroCodec Decoder
3 *
4 * Copyright (c) 2012, Derek Buitenhuis
5 *
6 * Permission to use, copy, modify, and/or distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <zlib.h>
20
21 #include "avcodec.h"
22 #include "libavutil/common.h"
23
24 typedef struct {
25 AVFrame previous_frame;
26 z_stream zstream;
27 int size;
28 } ZeroCodecContext;
29
30 static int zerocodec_decode_frame(AVCodecContext *avctx, void *data,
31 int *data_size, AVPacket *avpkt)
32 {
33 ZeroCodecContext *zc = avctx->priv_data;
34 AVFrame *pic = avctx->coded_frame;
35 AVFrame *prev_pic = &zc->previous_frame;
36 z_stream *zstream = &zc->zstream;
37 uint8_t *prev = prev_pic->data[0];
38 uint8_t *dst;
39 int i, j, zret;
40
41 pic->reference = 3;
42
43 if (avpkt->flags & AV_PKT_FLAG_KEY) {
44 pic->key_frame = 1;
45 pic->pict_type = AV_PICTURE_TYPE_I;
46 } else {
47 if (!prev) {
48 av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
49 return AVERROR_INVALIDDATA;
50 }
51 pic->key_frame = 0;
52 pic->pict_type = AV_PICTURE_TYPE_P;
53 }
54
55 zret = inflateReset(zstream);
56 if (zret != Z_OK) {
57 av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret);
58 return AVERROR_INVALIDDATA;
59 }
60
61 if (avctx->get_buffer(avctx, pic) < 0) {
62 av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n");
63 return AVERROR(ENOMEM);
64 }
65
66 zstream->next_in = avpkt->data;
67 zstream->avail_in = avpkt->size;
68
69 dst = pic->data[0];
70
71 /**
72 * ZeroCodec has very simple interframe compression. If a value
73 * is the same as the previous frame, set it to 0.
74 */
75
76 for (i = 0; i < avctx->height; i++) {
77 zstream->next_out = dst;
78 zstream->avail_out = avctx->width << 1;
79
80 zret = inflate(zstream, Z_SYNC_FLUSH);
81 if (zret != Z_OK && zret != Z_STREAM_END) {
82 avctx->release_buffer(avctx, pic);
83 av_log(avctx, AV_LOG_ERROR,
84 "Inflate failed with return code: %d.\n", zret);
85 return AVERROR_INVALIDDATA;
86 }
87
88 if (!(avpkt->flags & AV_PKT_FLAG_KEY))
89 for (j = 0; j < avctx->width << 1; j++)
90 dst[j] += prev[j] & -!dst[j];
91
92 prev += prev_pic->linesize[0];
93 dst += pic->linesize[0];
94 }
95
96 /* Release the previous buffer if need be */
97 if (prev_pic->data[0])
98 avctx->release_buffer(avctx, prev_pic);
99
100 *data_size = sizeof(AVFrame);
101 *(AVFrame *)data = *pic;
102
103 /* Store the previous frame for use later.
104 * FFSWAP ensures that e.g. pic->data is NULLed. */
105 FFSWAP(AVFrame, *pic, *prev_pic);
106
107 return avpkt->size;
108 }
109
110 static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
111 {
112 ZeroCodecContext *zc = avctx->priv_data;
113 AVFrame *prev_pic = &zc->previous_frame;
114
115 inflateEnd(&zc->zstream);
116
117 /* Release last frame */
118 if (prev_pic->data[0])
119 avctx->release_buffer(avctx, prev_pic);
120
121 av_freep(&avctx->coded_frame);
122
123 return 0;
124 }
125
126 static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
127 {
128 ZeroCodecContext *zc = avctx->priv_data;
129 z_stream *zstream = &zc->zstream;
130 int zret;
131
132 avctx->pix_fmt = AV_PIX_FMT_UYVY422;
133 avctx->bits_per_raw_sample = 8;
134
135 zc->size = avpicture_get_size(avctx->pix_fmt,
136 avctx->width, avctx->height);
137
138 zstream->zalloc = Z_NULL;
139 zstream->zfree = Z_NULL;
140 zstream->opaque = Z_NULL;
141
142 zret = inflateInit(zstream);
143 if (zret != Z_OK) {
144 av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d.\n", zret);
145 return AVERROR(ENOMEM);
146 }
147
148 avctx->coded_frame = avcodec_alloc_frame();
149 if (!avctx->coded_frame) {
150 av_log(avctx, AV_LOG_ERROR, "Could not allocate frame buffer.\n");
151 zerocodec_decode_close(avctx);
152 return AVERROR(ENOMEM);
153 }
154
155 return 0;
156 }
157
158 AVCodec ff_zerocodec_decoder = {
159 .type = AVMEDIA_TYPE_VIDEO,
160 .name = "zerocodec",
161 .id = AV_CODEC_ID_ZEROCODEC,
162 .priv_data_size = sizeof(ZeroCodecContext),
163 .init = zerocodec_decode_init,
164 .decode = zerocodec_decode_frame,
165 .close = zerocodec_decode_close,
166 .capabilities = CODEC_CAP_DR1,
167 .long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"),
168 };