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 "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  return AVERROR(ENOMEM);
136 
137  return 0;
138 }
139 
141 {
142  ZeroCodecContext *zc = avctx->priv_data;
143 
145 }
146 
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),
156  .close = zerocodec_decode_close,
157  .capabilities = AV_CODEC_CAP_DR1,
158  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
160 };
AVCodec
AVCodec.
Definition: codec.h:197
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:41
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
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:203
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:369
data
const char data[16]
Definition: mxf.c:142
zerocodec_decode_close
static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
Definition: zerocodec.c:103
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:410
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:332
ff_zerocodec_decoder
AVCodec ff_zerocodec_decoder
Definition: zerocodec.c:147
zerocodec_decode_frame
static int zerocodec_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: zerocodec.c:30
zerocodec_decode_flush
static void zerocodec_decode_flush(AVCodecContext *avctx)
Definition: zerocodec.c:140
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:198
AVFrame::key_frame
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:396
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
av_cold
#define av_cold
Definition: attributes.h:90
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
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:514
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1747
zerocodec_decode_init
static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
Definition: zerocodec.c:114
flush
static void flush(AVCodecContext *avctx)
Definition: aacdec_template.c:592
AV_CODEC_ID_ZEROCODEC
@ AV_CODEC_ID_ZEROCODEC
Definition: codec_id.h:210
AVCodec::type
enum AVMediaType type
Definition: codec.h:210
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1900
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:401
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:370
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
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:443
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:375
i
int i
Definition: input.c:407
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: internal.h:49
common.h
uint8_t
uint8_t
Definition: audio_convert.c:194
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
AVCodecContext::height
int height
Definition: avcodec.h:709
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:746
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:25
AVCodecContext
main external API structure.
Definition: avcodec.h:536
ZeroCodecContext::previous_frame
AVFrame * previous_frame
Definition: zerocodec.c:26
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:563
AVPacket
This structure stores compressed data.
Definition: packet.h:346
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:709
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:349
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
ZeroCodecContext::zstream
z_stream zstream
Definition: zerocodec.c:27