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zerocodec.c
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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 {
27  z_stream zstream;
29 
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;
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;
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 
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 
104 {
105  ZeroCodecContext *zc = avctx->priv_data;
106 
108 
109  inflateEnd(&zc->zstream);
110 
111  return 0;
112 }
113 
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 
134  if (!zc->previous_frame) {
135  zerocodec_decode_close(avctx);
136  return AVERROR(ENOMEM);
137  }
138 
139  return 0;
140 }
141 
144  .name = "zerocodec",
145  .long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"),
146  .id = AV_CODEC_ID_ZEROCODEC,
147  .priv_data_size = sizeof(ZeroCodecContext),
150  .close = zerocodec_decode_close,
151  .capabilities = AV_CODEC_CAP_DR1,
152 };
packed YUV 4:2:2, 16bpp, Cb Y0 Cr Y1
Definition: pixfmt.h:82
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:180
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1576
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1868
z_stream zstream
Definition: zerocodec.c:27
enum AVMediaType type
Definition: avcodec.h:3545
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:3040
AVCodec.
Definition: avcodec.h:3532
uint8_t
#define av_cold
Definition: attributes.h:82
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:140
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:374
static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
Definition: zerocodec.c:103
uint8_t * data
Definition: avcodec.h:1575
static void inflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord)
Definition: vf_neighbor.c:129
#define av_log(a,...)
static int zerocodec_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: zerocodec.c:30
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1607
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:153
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1581
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:254
int width
picture width / height.
Definition: avcodec.h:1827
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:211
main external API structure.
Definition: avcodec.h:1640
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:928
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:481
AVFrame * previous_frame
Definition: zerocodec.c:26
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:194
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:722
common internal api header.
common internal and external API header
void * priv_data
Definition: avcodec.h:1682
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:249
static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
Definition: zerocodec.c:114
This structure stores compressed data.
Definition: avcodec.h:1552
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:1336
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:951
for(j=16;j >0;--j)
AVCodec ff_zerocodec_decoder
Definition: zerocodec.c:142
Predicted.
Definition: avutil.h:267