4 * Copyright (c) 2012, Derek Buitenhuis
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.
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.
23 #include "libavutil/common.h"
26 AVFrame *previous_frame;
30 static int zerocodec_decode_frame(AVCodecContext *avctx, void *data,
31 int *got_frame, AVPacket *avpkt)
33 ZeroCodecContext *zc = avctx->priv_data;
35 AVFrame *prev_pic = zc->previous_frame;
36 z_stream *zstream = &zc->zstream;
37 uint8_t *prev = prev_pic->data[0];
41 if (avpkt->flags & AV_PKT_FLAG_KEY) {
43 pic->pict_type = AV_PICTURE_TYPE_I;
46 av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
47 return AVERROR_INVALIDDATA;
50 prev += (avctx->height - 1) * prev_pic->linesize[0];
53 pic->pict_type = AV_PICTURE_TYPE_P;
56 zret = inflateReset(zstream);
58 av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret);
59 return AVERROR_INVALIDDATA;
62 if (ff_get_buffer(avctx, pic, AV_GET_BUFFER_FLAG_REF) < 0) {
63 av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n");
64 return AVERROR(ENOMEM);
67 zstream->next_in = avpkt->data;
68 zstream->avail_in = avpkt->size;
70 dst = pic->data[0] + (avctx->height - 1) * pic->linesize[0];
73 * ZeroCodec has very simple interframe compression. If a value
74 * is the same as the previous frame, set it to 0.
77 for (i = 0; i < avctx->height; i++) {
78 zstream->next_out = dst;
79 zstream->avail_out = avctx->width << 1;
81 zret = inflate(zstream, Z_SYNC_FLUSH);
82 if (zret != Z_OK && zret != Z_STREAM_END) {
83 av_log(avctx, AV_LOG_ERROR,
84 "Inflate failed with return code: %d.\n", zret);
85 return AVERROR_INVALIDDATA;
88 if (!(avpkt->flags & AV_PKT_FLAG_KEY))
89 for (j = 0; j < avctx->width << 1; j++)
90 dst[j] += prev[j] & -!dst[j];
92 prev -= prev_pic->linesize[0];
93 dst -= pic->linesize[0];
96 av_frame_unref(zc->previous_frame);
97 if ((ret = av_frame_ref(zc->previous_frame, pic)) < 0)
105 static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
107 ZeroCodecContext *zc = avctx->priv_data;
109 av_frame_free(&zc->previous_frame);
111 inflateEnd(&zc->zstream);
116 static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
118 ZeroCodecContext *zc = avctx->priv_data;
119 z_stream *zstream = &zc->zstream;
122 avctx->pix_fmt = AV_PIX_FMT_UYVY422;
123 avctx->bits_per_raw_sample = 8;
125 zstream->zalloc = Z_NULL;
126 zstream->zfree = Z_NULL;
127 zstream->opaque = Z_NULL;
129 zret = inflateInit(zstream);
131 av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d.\n", zret);
132 return AVERROR(ENOMEM);
135 zc->previous_frame = av_frame_alloc();
136 if (!zc->previous_frame) {
137 zerocodec_decode_close(avctx);
138 return AVERROR(ENOMEM);
144 AVCodec ff_zerocodec_decoder = {
145 .type = AVMEDIA_TYPE_VIDEO,
147 .long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"),
148 .id = AV_CODEC_ID_ZEROCODEC,
149 .priv_data_size = sizeof(ZeroCodecContext),
150 .init = zerocodec_decode_init,
151 .decode = zerocodec_decode_frame,
152 .close = zerocodec_decode_close,
153 .capabilities = CODEC_CAP_DR1,