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dcadec.h
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1 /*
2  * Copyright (C) 2016 foo86
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
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19  */
20 
21 #ifndef AVCODEC_DCADEC_H
22 #define AVCODEC_DCADEC_H
23 
24 #include "libavutil/common.h"
25 #include "libavutil/crc.h"
26 #include "libavutil/float_dsp.h"
27 
28 #include "avcodec.h"
29 #include "get_bits.h"
30 #include "dca.h"
31 #include "dcadsp.h"
32 #include "dca_core.h"
33 #include "dca_exss.h"
34 #include "dca_xll.h"
35 #include "dca_lbr.h"
36 
37 #define DCA_PACKET_CORE 0x01
38 #define DCA_PACKET_EXSS 0x02
39 #define DCA_PACKET_XLL 0x04
40 #define DCA_PACKET_LBR 0x08
41 #define DCA_PACKET_MASK 0x0f
42 
43 #define DCA_PACKET_RECOVERY 0x10 ///< Sync error recovery flag
44 #define DCA_PACKET_RESIDUAL 0x20 ///< Core valid for residual decoding
45 
46 typedef struct DCAContext {
47  const AVClass *class; ///< class for AVOptions
49 
50  DCACoreDecoder core; ///< Core decoder context
51  DCAExssParser exss; ///< EXSS parser context
52  DCAXllDecoder xll; ///< XLL decoder context
53  DCALbrDecoder lbr; ///< LBR decoder context
54 
56 
57  const AVCRC *crctab;
58 
59  uint8_t *buffer; ///< Packet buffer
60  unsigned int buffer_size;
61 
62  int packet; ///< Packet flags
63 
64  int request_channel_layout; ///< Converted from avctx.request_channel_layout
65  int core_only; ///< Core only decoding flag
66 } DCAContext;
67 
68 int ff_dca_set_channel_layout(AVCodecContext *avctx, int *ch_remap, int dca_mask);
69 
71  int *coeff_l, int nsamples, int ch_mask);
72 void ff_dca_downmix_to_stereo_float(AVFloatDSPContext *fdsp, float **samples,
73  int *coeff_l, int nsamples, int ch_mask);
74 
75 static inline int ff_dca_check_crc(AVCodecContext *avctx, GetBitContext *s,
76  int p1, int p2)
77 {
78  DCAContext *dca = avctx->priv_data;
79 
80  if (!(avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL)))
81  return 0;
82  if (((p1 | p2) & 7) || p1 < 0 || p2 > s->size_in_bits || p2 - p1 < 16)
83  return -1;
84  if (av_crc(dca->crctab, 0xffff, s->buffer + p1 / 8, (p2 - p1) / 8))
85  return -1;
86  return 0;
87 }
88 
89 static inline int ff_dca_seek_bits(GetBitContext *s, int p)
90 {
91  if (p < get_bits_count(s) || p > s->size_in_bits)
92  return -1;
93  skip_bits_long(s, p - get_bits_count(s));
94  return 0;
95 }
96 
97 #endif
static int ff_dca_seek_bits(GetBitContext *s, int p)
Definition: dcadec.h:89
const char * s
Definition: avisynth_c.h:768
DCACoreDecoder core
Core decoder context.
Definition: dcadec.h:50
static void skip_bits_long(GetBitContext *s, int n)
Definition: get_bits.h:204
const uint8_t * buffer
Definition: get_bits.h:56
int core_only
Core only decoding flag.
Definition: dcadec.h:65
int packet
Packet flags.
Definition: dcadec.h:62
uint8_t * buffer
Packet buffer.
Definition: dcadec.h:59
uint8_t
Public header for CRC hash function implementation.
static int ff_dca_check_crc(AVCodecContext *avctx, GetBitContext *s, int p1, int p2)
Definition: dcadec.h:75
void ff_dca_downmix_to_stereo_float(AVFloatDSPContext *fdsp, float **samples, int *coeff_l, int nsamples, int ch_mask)
Definition: dcadec.c:110
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:199
bitstream reader API header.
AVCodecContext * avctx
Definition: dcadec.h:48
DCALbrDecoder lbr
LBR decoder context.
Definition: dcadec.h:53
DCAExssParser exss
EXSS parser context.
Definition: dcadec.h:51
void ff_dca_downmix_to_stereo_fixed(DCADSPContext *dcadsp, int32_t **samples, int *coeff_l, int nsamples, int ch_mask)
Definition: dcadec.c:79
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2626
const AVCRC * crctab
Definition: dcadec.h:57
int size_in_bits
Definition: get_bits.h:58
int32_t
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
Definition: crc.c:366
DCAXllDecoder xll
XLL decoder context.
Definition: dcadec.h:52
int ff_dca_set_channel_layout(AVCodecContext *avctx, int *ch_remap, int dca_mask)
Definition: dcadec.c:32
Libavcodec external API header.
main external API structure.
Definition: avcodec.h:1502
#define AV_EF_CAREFUL
consider things that violate the spec, are fast to calculate and have not been seen in the wild as er...
Definition: avcodec.h:2640
Describe the class of an AVClass context structure.
Definition: log.h:67
#define AV_EF_CRCCHECK
Verify checksums embedded in the bitstream (could be of either encoded or decoded data...
Definition: avcodec.h:2634
DCADSPContext dcadsp
Definition: dcadec.h:55
common internal and external API header
int request_channel_layout
Converted from avctx.request_channel_layout.
Definition: dcadec.h:64
void * priv_data
Definition: avcodec.h:1529
unsigned int buffer_size
Definition: dcadec.h:60
uint32_t AVCRC
Definition: crc.h:47