FFmpeg
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 "codec_internal.h"
23 #include "decode.h"
24 #include "zlib_wrapper.h"
25 #include "libavutil/common.h"
26 
27 typedef struct ZeroCodecContext {
31 
33  int *got_frame, AVPacket *avpkt)
34 {
35  ZeroCodecContext *zc = avctx->priv_data;
36  AVFrame *prev_pic = zc->previous_frame;
37  z_stream *const zstream = &zc->zstream.zstream;
38  uint8_t *prev = prev_pic->data[0];
39  uint8_t *dst;
40  int i, j, zret, ret;
41 
42  if (avpkt->flags & AV_PKT_FLAG_KEY) {
43  pic->key_frame = 1;
45  } else {
46  if (!prev) {
47  av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
48  return AVERROR_INVALIDDATA;
49  }
50 
51  prev += (avctx->height - 1) * prev_pic->linesize[0];
52 
53  pic->key_frame = 0;
55  }
56 
57  zret = inflateReset(zstream);
58  if (zret != Z_OK) {
59  av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret);
60  return AVERROR_INVALIDDATA;
61  }
62 
63  if ((ret = ff_get_buffer(avctx, pic, AV_GET_BUFFER_FLAG_REF)) < 0)
64  return ret;
65 
66  zstream->next_in = avpkt->data;
67  zstream->avail_in = avpkt->size;
68 
69  dst = pic->data[0] + (avctx->height - 1) * pic->linesize[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  av_log(avctx, AV_LOG_ERROR,
83  "Inflate failed with return code: %d.\n", zret);
84  return AVERROR_INVALIDDATA;
85  }
86 
87  if (!(avpkt->flags & AV_PKT_FLAG_KEY)) {
88  for (j = 0; j < avctx->width << 1; j++)
89  dst[j] += prev[j] & -!dst[j];
90  prev -= prev_pic->linesize[0];
91  }
92 
93  dst -= pic->linesize[0];
94  }
95 
97  if ((ret = av_frame_ref(zc->previous_frame, pic)) < 0)
98  return ret;
99 
100  *got_frame = 1;
101 
102  return avpkt->size;
103 }
104 
106 {
107  ZeroCodecContext *zc = avctx->priv_data;
108 
110 
111  ff_inflate_end(&zc->zstream);
112 
113  return 0;
114 }
115 
117 {
118  ZeroCodecContext *zc = avctx->priv_data;
119 
120  avctx->pix_fmt = AV_PIX_FMT_UYVY422;
121  avctx->bits_per_raw_sample = 8;
122 
124  if (!zc->previous_frame)
125  return AVERROR(ENOMEM);
126 
127  return ff_inflate_init(&zc->zstream, avctx);
128 }
129 
131 {
132  ZeroCodecContext *zc = avctx->priv_data;
133 
135 }
136 
139  .p.name = "zerocodec",
140  CODEC_LONG_NAME("ZeroCodec Lossless Video"),
141  .p.id = AV_CODEC_ID_ZEROCODEC,
142  .priv_data_size = sizeof(ZeroCodecContext),
145  .flush = zerocodec_decode_flush,
146  .close = zerocodec_decode_close,
147  .p.capabilities = AV_CODEC_CAP_DR1,
148  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
149 };
FF_CODEC_CAP_INIT_CLEANUP
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: codec_internal.h:42
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:116
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
AVPacket::data
uint8_t * data
Definition: packet.h:374
FFCodec
Definition: codec_internal.h:119
FFZStream::zstream
z_stream zstream
Definition: zlib_wrapper.h:28
zerocodec_decode_close
static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
Definition: zerocodec.c:105
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:346
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:123
zerocodec_decode_flush
static void zerocodec_decode_flush(AVCodecContext *avctx)
Definition: zerocodec.c:130
inflate
static void inflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord, int maxc)
Definition: vf_neighbor.c:195
AVFrame::key_frame
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:417
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:104
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
zlib_wrapper.h
av_cold
#define av_cold
Definition: attributes.h:90
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:298
AV_GET_BUFFER_FLAG_REF
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:376
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts_bsf.c:363
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1451
decode.h
zerocodec_decode_frame
static int zerocodec_decode_frame(AVCodecContext *avctx, AVFrame *pic, int *got_frame, AVPacket *avpkt)
Definition: zerocodec.c:32
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:264
zerocodec_decode_init
static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
Definition: zerocodec.c:116
AV_CODEC_ID_ZEROCODEC
@ AV_CODEC_ID_ZEROCODEC
Definition: codec_id.h:213
AVCodec::type
enum AVMediaType type
Definition: codec.h:217
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
ff_zerocodec_decoder
const FFCodec ff_zerocodec_decoder
Definition: zerocodec.c:137
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1450
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:422
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:375
av_frame_ref
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:353
codec_internal.h
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
ZeroCodecContext::zstream
FFZStream zstream
Definition: zerocodec.c:29
common.h
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:487
ff_inflate_end
void ff_inflate_end(FFZStream *zstream)
Wrapper around inflateEnd().
AVCodecContext::height
int height
Definition: avcodec.h:571
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:608
avcodec.h
ret
ret
Definition: filter_design.txt:187
AV_PIX_FMT_UYVY422
@ AV_PIX_FMT_UYVY422
packed YUV 4:2:2, 16bpp, Cb Y0 Cr Y1
Definition: pixfmt.h:81
ZeroCodecContext
Definition: zerocodec.c:27
AVCodecContext
main external API structure.
Definition: avcodec.h:398
ZeroCodecContext::previous_frame
AVFrame * previous_frame
Definition: zerocodec.c:28
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
FFZStream
Definition: zlib_wrapper.h:27
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:425
AVPacket
This structure stores compressed data.
Definition: packet.h:351
ff_inflate_init
int ff_inflate_init(FFZStream *zstream, void *logctx)
Wrapper around inflateInit().
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:571
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:370
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61