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 "internal.h"
23 #include "libavutil/common.h"
24
25 typedef struct ZeroCodecContext {
26 AVFrame *previous_frame;
27 z_stream zstream;
28 } ZeroCodecContext;
29
zerocodec_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)30 static int zerocodec_decode_frame(AVCodecContext *avctx, void *data,
31 int *got_frame, AVPacket *avpkt)
32 {
33 ZeroCodecContext *zc = avctx->priv_data;
34 AVFrame *pic = data;
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, ret;
40
41 if (avpkt->flags & AV_PKT_FLAG_KEY) {
42 pic->key_frame = 1;
43 pic->pict_type = AV_PICTURE_TYPE_I;
44 } else {
45 if (!prev) {
46 av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
47 return AVERROR_INVALIDDATA;
48 }
49
50 prev += (avctx->height - 1) * prev_pic->linesize[0];
51
52 pic->key_frame = 0;
53 pic->pict_type = AV_PICTURE_TYPE_P;
54 }
55
56 zret = inflateReset(zstream);
57 if (zret != Z_OK) {
58 av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret);
59 return AVERROR_INVALIDDATA;
60 }
61
62 if ((ret = ff_get_buffer(avctx, pic, AV_GET_BUFFER_FLAG_REF)) < 0)
63 return ret;
64
65 zstream->next_in = avpkt->data;
66 zstream->avail_in = avpkt->size;
67
68 dst = pic->data[0] + (avctx->height - 1) * pic->linesize[0];
69
70 /**
71 * ZeroCodec has very simple interframe compression. If a value
72 * is the same as the previous frame, set it to 0.
73 */
74
75 for (i = 0; i < avctx->height; i++) {
76 zstream->next_out = dst;
77 zstream->avail_out = avctx->width << 1;
78
79 zret = inflate(zstream, Z_SYNC_FLUSH);
80 if (zret != Z_OK && zret != Z_STREAM_END) {
81 av_log(avctx, AV_LOG_ERROR,
82 "Inflate failed with return code: %d.\n", zret);
83 return AVERROR_INVALIDDATA;
84 }
85
86 if (!(avpkt->flags & AV_PKT_FLAG_KEY))
87 for (j = 0; j < avctx->width << 1; j++)
88 dst[j] += prev[j] & -!dst[j];
89
90 prev -= prev_pic->linesize[0];
91 dst -= pic->linesize[0];
92 }
93
94 av_frame_unref(zc->previous_frame);
95 if ((ret = av_frame_ref(zc->previous_frame, pic)) < 0)
96 return ret;
97
98 *got_frame = 1;
99
100 return avpkt->size;
101 }
102
zerocodec_decode_close(AVCodecContext * avctx)103 static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
104 {
105 ZeroCodecContext *zc = avctx->priv_data;
106
107 av_frame_free(&zc->previous_frame);
108
109 inflateEnd(&zc->zstream);
110
111 return 0;
112 }
113
zerocodec_decode_init(AVCodecContext * avctx)114 static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
115 {
116 ZeroCodecContext *zc = avctx->priv_data;
117 z_stream *zstream = &zc->zstream;
118 int zret;
119
120 avctx->pix_fmt = AV_PIX_FMT_UYVY422;
121 avctx->bits_per_raw_sample = 8;
122
123 zstream->zalloc = Z_NULL;
124 zstream->zfree = Z_NULL;
125 zstream->opaque = Z_NULL;
126
127 zret = inflateInit(zstream);
128 if (zret != Z_OK) {
129 av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d.\n", zret);
130 return AVERROR(ENOMEM);
131 }
132
133 zc->previous_frame = av_frame_alloc();
134 if (!zc->previous_frame)
135 return AVERROR(ENOMEM);
136
137 return 0;
138 }
139
zerocodec_decode_flush(AVCodecContext * avctx)140 static void zerocodec_decode_flush(AVCodecContext *avctx)
141 {
142 ZeroCodecContext *zc = avctx->priv_data;
143
144 av_frame_unref(zc->previous_frame);
145 }
146
147 AVCodec ff_zerocodec_decoder = {
148 .type = AVMEDIA_TYPE_VIDEO,
149 .name = "zerocodec",
150 .long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"),
151 .id = AV_CODEC_ID_ZEROCODEC,
152 .priv_data_size = sizeof(ZeroCodecContext),
153 .init = zerocodec_decode_init,
154 .decode = zerocodec_decode_frame,
155 .flush = zerocodec_decode_flush,
156 .close = zerocodec_decode_close,
157 .capabilities = AV_CODEC_CAP_DR1,
158 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
159 FF_CODEC_CAP_INIT_CLEANUP,
160 };
161