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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 "get_bits.h"
29 #include "internal.h"
30 
31 static int decode_frame(AVCodecContext *avctx,
32  void *data, int *got_frame,
33  AVPacket *avpkt)
34 {
35  const uint8_t *buf = avpkt->data;
36  int buf_size = avpkt->size;
37  GetBitContext gb;
38  AVFrame * const p = data;
39  int x, y, ret;
40 
41  if (avctx->height <= 0 || avctx->width <= 0) {
42  av_log(avctx, AV_LOG_ERROR, "Invalid width or height\n");
43  return AVERROR_INVALIDDATA;
44  }
45 
46  if (buf_size / avctx->height < avctx->width) {
47  av_log(avctx, AV_LOG_ERROR,
48  "Resolution larger than buffer size. Invalid header?\n");
49  return AVERROR_INVALIDDATA;
50  }
51 
52  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
53  return ret;
55  p->key_frame = 1;
56 
57  init_get_bits(&gb, buf, buf_size * 8);
58 
59  for (y = 0; y < avctx->height; y++) {
60  uint8_t *luma = &p->data[0][y * p->linesize[0]];
61  uint8_t *cb = &p->data[1][y * p->linesize[1]];
62  uint8_t *cr = &p->data[2][y * p->linesize[2]];
63  for (x = 0; x < avctx->width; x += 4) {
64  luma[3] = (get_bits(&gb, 5)*33) >> 2;
65  luma[2] = (get_bits(&gb, 5)*33) >> 2;
66  luma[1] = (get_bits(&gb, 5)*33) >> 2;
67  luma[0] = (get_bits(&gb, 5)*33) >> 2;
68  luma += 4;
69  *(cb++) = get_bits(&gb, 6) << 2;
70  *(cr++) = get_bits(&gb, 6) << 2;
71  }
72  }
73 
74  *got_frame = 1;
75 
76  return buf_size;
77 }
78 
80 {
81  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
82  return 0;
83 }
84 
86  .name = "cljr",
87  .long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
88  .type = AVMEDIA_TYPE_VIDEO,
89  .id = AV_CODEC_ID_CLJR,
90  .init = decode_init,
91  .decode = decode_frame,
92  .capabilities = AV_CODEC_CAP_DR1,
93 };
94 
#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:201
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:261
int size
Definition: avcodec.h:1401
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1697
AVCodec.
Definition: avcodec.h:3351
static double cb(void *priv, double x, double y)
Definition: vf_geq.c:106
uint8_t
#define av_cold
Definition: attributes.h:82
uint8_t * data
Definition: avcodec.h:1400
bitstream reader API header.
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3358
AVCodec ff_cljr_decoder
Definition: cljrdec.c:85
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:284
int width
picture width / height.
Definition: avcodec.h:1660
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:232
static av_cold int decode_init(AVCodecContext *avctx)
Definition: cljrdec.c:79
main external API structure.
Definition: avcodec.h:1488
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1886
void * buf
Definition: avisynth_c.h:690
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:425
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:215
common internal api header.
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:69
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: cljrdec.c:31
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:279
static double cr(void *priv, double x, double y)
Definition: vf_geq.c:107
This structure stores compressed data.
Definition: avcodec.h:1377
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:956