cljr.c
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1 /*
2  * Cirrus Logic AccuPak (CLJR) codec
3  * Copyright (c) 2003 Alex Beregszaszi
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
27 #include "avcodec.h"
28 #include "get_bits.h"
29 #include "put_bits.h"
30 
31 typedef struct CLJRContext {
33 } CLJRContext;
34 
36 {
37  CLJRContext * const a = avctx->priv_data;
38 
39  avctx->coded_frame = &a->picture;
40 
41  return 0;
42 }
43 
44 #if CONFIG_CLJR_DECODER
45 static int decode_frame(AVCodecContext *avctx,
46  void *data, int *data_size,
47  AVPacket *avpkt)
48 {
49  const uint8_t *buf = avpkt->data;
50  int buf_size = avpkt->size;
51  CLJRContext * const a = avctx->priv_data;
52  GetBitContext gb;
53  AVFrame *picture = data;
54  AVFrame * const p = &a->picture;
55  int x, y;
56 
57  if (p->data[0])
58  avctx->release_buffer(avctx, p);
59 
60  if (avctx->height <= 0 || avctx->width <= 0) {
61  av_log(avctx, AV_LOG_ERROR, "Invalid width or height\n");
62  return AVERROR_INVALIDDATA;
63  }
64 
65  if (buf_size < avctx->height * avctx->width) {
66  av_log(avctx, AV_LOG_ERROR,
67  "Resolution larger than buffer size. Invalid header?\n");
68  return AVERROR_INVALIDDATA;
69  }
70 
71  p->reference = 0;
72  if (avctx->get_buffer(avctx, p) < 0) {
73  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
74  return -1;
75  }
77  p->key_frame = 1;
78 
79  init_get_bits(&gb, buf, buf_size * 8);
80 
81  for (y = 0; y < avctx->height; y++) {
82  uint8_t *luma = &a->picture.data[0][y * a->picture.linesize[0]];
83  uint8_t *cb = &a->picture.data[1][y * a->picture.linesize[1]];
84  uint8_t *cr = &a->picture.data[2][y * a->picture.linesize[2]];
85  for (x = 0; x < avctx->width; x += 4) {
86  luma[3] = get_bits(&gb, 5) << 3;
87  luma[2] = get_bits(&gb, 5) << 3;
88  luma[1] = get_bits(&gb, 5) << 3;
89  luma[0] = get_bits(&gb, 5) << 3;
90  luma += 4;
91  *(cb++) = get_bits(&gb, 6) << 2;
92  *(cr++) = get_bits(&gb, 6) << 2;
93  }
94  }
95 
96  *picture = a->picture;
97  *data_size = sizeof(AVPicture);
98 
99  return buf_size;
100 }
101 
102 static av_cold int decode_init(AVCodecContext *avctx)
103 {
104  avctx->pix_fmt = PIX_FMT_YUV411P;
105  return common_init(avctx);
106 }
107 
108 static av_cold int decode_end(AVCodecContext *avctx)
109 {
110  CLJRContext *a = avctx->priv_data;
111 
112  if (a->picture.data[0])
113  avctx->release_buffer(avctx, &a->picture);
114  return 0;
115 }
116 
117 AVCodec ff_cljr_decoder = {
118  .name = "cljr",
119  .type = AVMEDIA_TYPE_VIDEO,
120  .id = CODEC_ID_CLJR,
121  .priv_data_size = sizeof(CLJRContext),
122  .init = decode_init,
123  .close = decode_end,
124  .decode = decode_frame,
125  .capabilities = CODEC_CAP_DR1,
126  .long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
127 };
128 #endif
129 
130 #if CONFIG_CLJR_ENCODER
131 static int encode_frame(AVCodecContext *avctx, unsigned char *buf,
132  int buf_size, void *data)
133 {
134  PutBitContext pb;
135  AVFrame *p = data;
136  int x, y;
137 
139  p->key_frame = 1;
140 
141  init_put_bits(&pb, buf, buf_size / 8);
142 
143  for (y = 0; y < avctx->height; y++) {
144  uint8_t *luma = &p->data[0][y * p->linesize[0]];
145  uint8_t *cb = &p->data[1][y * p->linesize[1]];
146  uint8_t *cr = &p->data[2][y * p->linesize[2]];
147  for (x = 0; x < avctx->width; x += 4) {
148  put_bits(&pb, 5, luma[3] >> 3);
149  put_bits(&pb, 5, luma[2] >> 3);
150  put_bits(&pb, 5, luma[1] >> 3);
151  put_bits(&pb, 5, luma[0] >> 3);
152  luma += 4;
153  put_bits(&pb, 6, *(cb++) >> 2);
154  put_bits(&pb, 6, *(cr++) >> 2);
155  }
156  }
157 
158  flush_put_bits(&pb);
159 
160  return put_bits_count(&pb) / 8;
161 }
162 
163 AVCodec ff_cljr_encoder = {
164  .name = "cljr",
165  .type = AVMEDIA_TYPE_VIDEO,
166  .id = CODEC_ID_CLJR,
167  .priv_data_size = sizeof(CLJRContext),
168  .init = common_init,
169  .encode = encode_frame,
170  .pix_fmts = (const enum PixelFormat[]) { PIX_FMT_YUV411P,
171  PIX_FMT_NONE },
172  .long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
173 };
174 #endif
int(* get_buffer)(struct AVCodecContext *c, AVFrame *pic)
Called at the beginning of each frame to get a buffer for it.
Definition: avcodec.h:1726
enum PixelFormat pix_fmt
Pixel format, see PIX_FMT_xxx.
Definition: avcodec.h:1426
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
Audio Video Frame.
Definition: avcodec.h:985
void(* release_buffer)(struct AVCodecContext *c, AVFrame *pic)
Called to release buffers which were allocated with get_buffer.
Definition: avcodec.h:1737
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:237
AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2000
int size
Definition: avcodec.h:909
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:71
AVCodec.
Definition: avcodec.h:3189
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:228
#define av_cold
Definition: attributes.h:71
const char data[16]
Definition: mxf.c:60
uint8_t * data
Definition: avcodec.h:908
static av_cold int decode_init(AVCodecContext *avctx)
Definition: 4xm.c:887
bitstream reader API header.
static int init(AVCodecParserContext *s)
Definition: h264_parser.c:336
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:719
struct CLJRContext CLJRContext
int reference
is this picture used as reference The values for this are the same as the MpegEncContext.picture_structure variable, that is 1->top field, 2->bottom field, 3->frame/both fields.
Definition: avcodec.h:1074
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:191
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:140
const char * name
Name of the codec implementation.
Definition: avcodec.h:3196
static void put_bits(PutBitContext *s, int n, unsigned int value)
Write up to 31 bits into a bitstream.
Definition: put_bits.h:136
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:70
static AVFrame * picture
enum AVPictureType pict_type
Picture type of the frame, see ?_TYPE below.
Definition: avcodec.h:1029
static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
Definition: 4xm.c:739
int width
picture width / height.
Definition: avcodec.h:1408
AVFrame picture
Definition: cljr.c:32
static av_cold int common_init(AVCodecContext *avctx)
Definition: cljr.c:35
external API header
int AC3_NAME() encode_frame(AVCodecContext *avctx, unsigned char *frame, int buf_size, void *data)
int linesize[AV_NUM_DATA_POINTERS]
Size, in bytes, of the data for each picture/channel plane.
Definition: avcodec.h:1008
main external API structure.
Definition: avcodec.h:1329
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:327
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:111
struct AVPicture AVPicture
four components are given, that's all.
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:354
static av_cold int decode_end(AVCodecContext *avctx)
Definition: 4xm.c:906
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: avcodec.h:997
int height
Definition: gxfenc.c:73
PixelFormat
Pixel format.
Definition: pixfmt.h:62
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:86
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:52
void * priv_data
Definition: avcodec.h:1531
int key_frame
1 -> keyframe, 0-> not
Definition: avcodec.h:1022
bitstream writer API