FFmpeg
cljrdec.c
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1 /*
2  * Cirrus Logic AccuPak (CLJR) decoder
3  * Copyright (c) 2003 Alex Beregszaszi
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  * Cirrus Logic AccuPak decoder.
25  */
26 
27 #include "avcodec.h"
28 #include "codec_internal.h"
29 #include "get_bits.h"
30 #include "internal.h"
31 
32 static int decode_frame(AVCodecContext *avctx, AVFrame *p,
33  int *got_frame, AVPacket *avpkt)
34 {
35  const uint8_t *buf = avpkt->data;
36  int buf_size = avpkt->size;
37  GetBitContext gb;
38  int x, y, ret;
39 
40  if (avctx->height <= 0 || avctx->width <= 0) {
41  av_log(avctx, AV_LOG_ERROR, "Invalid width or height\n");
42  return AVERROR_INVALIDDATA;
43  }
44 
45  if (buf_size / avctx->height < avctx->width) {
46  av_log(avctx, AV_LOG_ERROR,
47  "Resolution larger than buffer size. Invalid header?\n");
48  return AVERROR_INVALIDDATA;
49  }
50 
51  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
52  return ret;
54  p->key_frame = 1;
55 
56  init_get_bits(&gb, buf, buf_size * 8);
57 
58  for (y = 0; y < avctx->height; y++) {
59  uint8_t *luma = &p->data[0][y * p->linesize[0]];
60  uint8_t *cb = &p->data[1][y * p->linesize[1]];
61  uint8_t *cr = &p->data[2][y * p->linesize[2]];
62  for (x = 0; x < avctx->width; x += 4) {
63  luma[3] = (get_bits(&gb, 5)*33) >> 2;
64  luma[2] = (get_bits(&gb, 5)*33) >> 2;
65  luma[1] = (get_bits(&gb, 5)*33) >> 2;
66  luma[0] = (get_bits(&gb, 5)*33) >> 2;
67  luma += 4;
68  *(cb++) = get_bits(&gb, 6) << 2;
69  *(cr++) = get_bits(&gb, 6) << 2;
70  }
71  }
72 
73  *got_frame = 1;
74 
75  return buf_size;
76 }
77 
79 {
80  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
81  return 0;
82 }
83 
85  .p.name = "cljr",
86  .p.long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
87  .p.type = AVMEDIA_TYPE_VIDEO,
88  .p.id = AV_CODEC_ID_CLJR,
89  .init = decode_init,
91  .p.capabilities = AV_CODEC_CAP_DR1,
92 };
93 
cb
static double cb(void *priv, double x, double y)
Definition: vf_geq.c:239
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:374
FFCodec
Definition: codec_internal.h:118
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:649
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:346
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:122
GetBitContext
Definition: get_bits.h:61
AVFrame::key_frame
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:417
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:260
decode_frame
static int decode_frame(AVCodecContext *avctx, AVFrame *p, int *got_frame, AVPacket *avpkt)
Definition: cljrdec.c:32
get_bits.h
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:422
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1462
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
AV_CODEC_ID_CLJR
@ AV_CODEC_ID_CLJR
Definition: codec_id.h:86
AVPacket::size
int size
Definition: packet.h:375
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
codec_internal.h
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: cljrdec.c:78
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:211
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
AVCodecContext
main external API structure.
Definition: avcodec.h:398
ff_cljr_decoder
const FFCodec ff_cljr_decoder
Definition: cljrdec.c:84
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVPacket
This structure stores compressed data.
Definition: packet.h:351
cr
static double cr(void *priv, double x, double y)
Definition: vf_geq.c:240
AV_PIX_FMT_YUV411P
@ AV_PIX_FMT_YUV411P
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:73
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