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vcr1.c
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1 /*
2  * ATI VCR1 codec
3  * Copyright (c) 2003 Michael Niedermayer
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * ATI VCR1 codec
25  */
26 
27 #include "avcodec.h"
28 #include "internal.h"
29 #include "libavutil/avassert.h"
30 #include "libavutil/internal.h"
31 
32 typedef struct VCR1Context {
33  int delta[16];
34  int offset[4];
35 } VCR1Context;
36 
38 {
39  avctx->pix_fmt = AV_PIX_FMT_YUV410P;
40 
41  if (avctx->width % 8 || avctx->height%4) {
42  avpriv_request_sample(avctx, "odd dimensions (%d x %d) support", avctx->width, avctx->height);
43  return AVERROR_INVALIDDATA;
44  }
45 
46  return 0;
47 }
48 
49 static int vcr1_decode_frame(AVCodecContext *avctx, void *data,
50  int *got_frame, AVPacket *avpkt)
51 {
52  VCR1Context *const a = avctx->priv_data;
53  AVFrame *const p = data;
54  const uint8_t *bytestream = avpkt->data;
55  const uint8_t *bytestream_end = bytestream + avpkt->size;
56  int i, x, y, ret;
57 
58  if(avpkt->size < 32 + avctx->height + avctx->width*avctx->height*5/8){
59  av_log(avctx, AV_LOG_ERROR, "Insufficient input data. %d < %d\n", avpkt->size , 32 + avctx->height + avctx->width*avctx->height*5/8);
60  return AVERROR(EINVAL);
61  }
62 
63  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
64  return ret;
66  p->key_frame = 1;
67 
68  for (i = 0; i < 16; i++) {
69  a->delta[i] = *bytestream++;
70  bytestream++;
71  }
72 
73  for (y = 0; y < avctx->height; y++) {
74  int offset;
75  uint8_t *luma = &p->data[0][y * p->linesize[0]];
76 
77  if ((y & 3) == 0) {
78  uint8_t *cb = &p->data[1][(y >> 2) * p->linesize[1]];
79  uint8_t *cr = &p->data[2][(y >> 2) * p->linesize[2]];
80 
81  av_assert0 (bytestream_end - bytestream >= 4 + avctx->width);
82 
83  for (i = 0; i < 4; i++)
84  a->offset[i] = *bytestream++;
85 
86  offset = a->offset[0] - a->delta[bytestream[2] & 0xF];
87  for (x = 0; x < avctx->width; x += 4) {
88  luma[0] = offset += a->delta[bytestream[2] & 0xF];
89  luma[1] = offset += a->delta[bytestream[2] >> 4];
90  luma[2] = offset += a->delta[bytestream[0] & 0xF];
91  luma[3] = offset += a->delta[bytestream[0] >> 4];
92  luma += 4;
93 
94  *cb++ = bytestream[3];
95  *cr++ = bytestream[1];
96 
97  bytestream += 4;
98  }
99  } else {
100  av_assert0 (bytestream_end - bytestream >= avctx->width / 2);
101 
102  offset = a->offset[y & 3] - a->delta[bytestream[2] & 0xF];
103 
104  for (x = 0; x < avctx->width; x += 8) {
105  luma[0] = offset += a->delta[bytestream[2] & 0xF];
106  luma[1] = offset += a->delta[bytestream[2] >> 4];
107  luma[2] = offset += a->delta[bytestream[3] & 0xF];
108  luma[3] = offset += a->delta[bytestream[3] >> 4];
109  luma[4] = offset += a->delta[bytestream[0] & 0xF];
110  luma[5] = offset += a->delta[bytestream[0] >> 4];
111  luma[6] = offset += a->delta[bytestream[1] & 0xF];
112  luma[7] = offset += a->delta[bytestream[1] >> 4];
113  luma += 8;
114  bytestream += 4;
115  }
116  }
117  }
118 
119  *got_frame = 1;
120 
121  return bytestream - avpkt->data;
122 }
123 
125  .name = "vcr1",
126  .long_name = NULL_IF_CONFIG_SMALL("ATI VCR1"),
127  .type = AVMEDIA_TYPE_VIDEO,
128  .id = AV_CODEC_ID_VCR1,
129  .priv_data_size = sizeof(VCR1Context),
132  .capabilities = AV_CODEC_CAP_DR1,
133 };
#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:184
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:1591
static av_cold int vcr1_decode_init(AVCodecContext *avctx)
Definition: vcr1.c:37
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1887
AVCodec.
Definition: avcodec.h:3573
int offset[4]
Definition: vcr1.c:34
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
static double cb(void *priv, double x, double y)
Definition: vf_geq.c:97
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
uint8_t
#define av_cold
Definition: attributes.h:82
uint8_t * data
Definition: avcodec.h:1590
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
simple assert() macros that are a bit more flexible than ISO C assert().
const char * name
Name of the codec implementation.
Definition: avcodec.h:3580
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
common internal API header
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:258
int width
picture width / height.
Definition: avcodec.h:1846
int delta[16]
Definition: vcr1.c:33
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:215
main external API structure.
Definition: avcodec.h:1659
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:928
planar YUV 4:1:0, 9bpp, (1 Cr & Cb sample per 4x4 Y samples)
Definition: pixfmt.h:68
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:752
AVCodec ff_vcr1_decoder
Definition: vcr1.c:124
common internal api header.
static int vcr1_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: vcr1.c:49
void * priv_data
Definition: avcodec.h:1701
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:253
static double cr(void *priv, double x, double y)
Definition: vf_geq.c:98
This structure stores compressed data.
Definition: avcodec.h:1567
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:958
for(j=16;j >0;--j)