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;
31 static int zerocodec_decode_frame(AVCodecContext *avctx, void *data,
32 int *got_frame, AVPacket *avpkt)
34 ZeroCodecContext *zc = avctx->priv_data;
35 AVFrame *pic = avctx->coded_frame;
36 AVFrame *prev_pic = &zc->previous_frame;
37 z_stream *zstream = &zc->zstream;
38 uint8_t *prev = prev_pic->data[0];
44 if (avpkt->flags & AV_PKT_FLAG_KEY) {
46 pic->pict_type = AV_PICTURE_TYPE_I;
49 av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
50 return AVERROR_INVALIDDATA;
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) < 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;
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 avctx->release_buffer(avctx, pic);
84 av_log(avctx, AV_LOG_ERROR,
85 "Inflate failed with return code: %d.\n", zret);
86 return AVERROR_INVALIDDATA;
89 if (!(avpkt->flags & AV_PKT_FLAG_KEY))
90 for (j = 0; j < avctx->width << 1; j++)
91 dst[j] += prev[j] & -!dst[j];
93 prev += prev_pic->linesize[0];
94 dst += pic->linesize[0];
97 /* Release the previous buffer if need be */
98 if (prev_pic->data[0])
99 avctx->release_buffer(avctx, prev_pic);
102 *(AVFrame *)data = *pic;
104 /* Store the previous frame for use later.
105 * FFSWAP ensures that e.g. pic->data is NULLed. */
106 FFSWAP(AVFrame, *pic, *prev_pic);
111 static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
113 ZeroCodecContext *zc = avctx->priv_data;
114 AVFrame *prev_pic = &zc->previous_frame;
116 inflateEnd(&zc->zstream);
118 /* Release last frame */
119 if (prev_pic->data[0])
120 avctx->release_buffer(avctx, prev_pic);
122 av_freep(&avctx->coded_frame);
127 static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
129 ZeroCodecContext *zc = avctx->priv_data;
130 z_stream *zstream = &zc->zstream;
133 avctx->pix_fmt = AV_PIX_FMT_UYVY422;
134 avctx->bits_per_raw_sample = 8;
136 zc->size = avpicture_get_size(avctx->pix_fmt,
137 avctx->width, avctx->height);
139 zstream->zalloc = Z_NULL;
140 zstream->zfree = Z_NULL;
141 zstream->opaque = Z_NULL;
143 zret = inflateInit(zstream);
145 av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d.\n", zret);
146 return AVERROR(ENOMEM);
149 avctx->coded_frame = avcodec_alloc_frame();
150 if (!avctx->coded_frame) {
151 av_log(avctx, AV_LOG_ERROR, "Could not allocate frame buffer.\n");
152 zerocodec_decode_close(avctx);
153 return AVERROR(ENOMEM);
159 AVCodec ff_zerocodec_decoder = {
160 .type = AVMEDIA_TYPE_VIDEO,
162 .id = AV_CODEC_ID_ZEROCODEC,
163 .priv_data_size = sizeof(ZeroCodecContext),
164 .init = zerocodec_decode_init,
165 .decode = zerocodec_decode_frame,
166 .close = zerocodec_decode_close,
167 .capabilities = CODEC_CAP_DR1,
168 .long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"),