FFmpeg: libavcodec/ac3dec_fixed.c Source File

FFmpeg

libavcodec

ac3dec_fixed.c

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1 /*

2 * Copyright (c) 2012

3 * MIPS Technologies, Inc., California.

4 *

5 * Redistribution and use in source and binary forms, with or without

6 * modification, are permitted provided that the following conditions

7 * are met:

8 * 1. Redistributions of source code must retain the above copyright

9 * notice, this list of conditions and the following disclaimer.

10 * 2. Redistributions in binary form must reproduce the above copyright

11 * notice, this list of conditions and the following disclaimer in the

12 * documentation and/or other materials provided with the distribution.

13 * 3. Neither the name of the MIPS Technologies, Inc., nor the names of its

14 * contributors may be used to endorse or promote products derived from

15 * this software without specific prior written permission.

16 *

17 * THIS SOFTWARE IS PROVIDED BY THE MIPS TECHNOLOGIES, INC. ``AS IS'' AND

18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

20 * ARE DISCLAIMED. IN NO EVENT SHALL THE MIPS TECHNOLOGIES, INC. BE LIABLE

21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

27 * SUCH DAMAGE.

28 *

29 * Author: Stanislav Ocovaj (socovaj@mips.com)

30 *

31 * AC3 fixed-point decoder for MIPS platforms

32 *

33 * This file is part of FFmpeg.

34 *

35 * FFmpeg is free software; you can redistribute it and/or

36 * modify it under the terms of the GNU Lesser General Public

37 * License as published by the Free Software Foundation; either

38 * version 2.1 of the License, or (at your option) any later version.

39 *

40 * FFmpeg is distributed in the hope that it will be useful,

41 * but WITHOUT ANY WARRANTY; without even the implied warranty of

42 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

43 * Lesser General Public License for more details.

44 *

45 * You should have received a copy of the GNU Lesser General Public

46 * License along with FFmpeg; if not, write to the Free Software

47 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

48 */

49

50 #define USE_FIXED 1

51 #include "ac3dec.h"

52 #include "codec_internal.h"

53 #define IMDCT_TYPE AV_TX_INT32_MDCT

54

55 #include "ac3dec.h"

56

57 static const int end_freq_inv_tab[8] =

58 {

59 50529027, 44278013, 39403370, 32292987, 27356480, 23729101, 20951060, 18755316

60 };

61

62 static void scale_coefs (

63 int32_t *dst,

64 const int32_t *src,

65 int dynrng,

66 int len)

67 {

68 int i, shift;

69 unsigned mul, round;

70 int temp, temp1, temp2, temp3, temp4, temp5, temp6, temp7;

71

72 mul = (dynrng & 0x1f) + 0x20;

73 shift = 4 - (sign_extend(dynrng, 9) >> 5);

74 if (shift > 0 ) {

75 round = 1 << (shift-1);

76 for (i=0; i<len; i+=8) {

77

78 temp = src[i] * mul;

79 temp1 = src[i+1] * mul;

80 temp = temp + round;

81 temp2 = src[i+2] * mul;

82

83 temp1 = temp1 + round;

84 dst[i] = temp >> shift;

85 temp3 = src[i+3] * mul;

86 temp2 = temp2 + round;

87

88 dst[i+1] = temp1 >> shift;

89 temp4 = src[i + 4] * mul;

90 temp3 = temp3 + round;

91 dst[i+2] = temp2 >> shift;

92

93 temp5 = src[i+5] * mul;

94 temp4 = temp4 + round;

95 dst[i+3] = temp3 >> shift;

96 temp6 = src[i+6] * mul;

97

98 dst[i+4] = temp4 >> shift;

99 temp5 = temp5 + round;

100 temp7 = src[i+7] * mul;

101 temp6 = temp6 + round;

102

103 dst[i+5] = temp5 >> shift;

104 temp7 = temp7 + round;

105 dst[i+6] = temp6 >> shift;

106 dst[i+7] = temp7 >> shift;

107

108 }

109 } else {

110 shift = -shift;

111 mul <<= shift;

112 for (i=0; i<len; i+=8) {

113

114 dst[i] = src[i ] * mul;

115 dst[i+1] = src[i+1] * mul;

116 dst[i+2] = src[i+2] * mul;

117 dst[i+3] = src[i+3] * mul;

118 dst[i+4] = src[i+4] * mul;

119 dst[i+5] = src[i+5] * mul;

120 dst[i+6] = src[i+6] * mul;

121 dst[i+7] = src[i+7] * mul;

122 }

123 }

124 }

125

126 /**

127 * Downmix samples from original signal to stereo or mono (this is for 16-bit samples

128 * and fixed point decoder - original (for 32-bit samples) is in ac3dsp.c).

129 */

130 static void ac3_downmix_c_fixed16(int16_t **samples, int16_t **matrix,

131 int out_ch, int in_ch, int len)

132 {

133 int i, j;

134 int v0, v1;

135 if (out_ch == 2) {

136 for (i = 0; i < len; i++) {

137 v0 = v1 = 0;

138 for (j = 0; j < in_ch; j++) {

139 v0 += samples[j][i] * matrix[0][j];

140 v1 += samples[j][i] * matrix[1][j];

141 }

142 samples[0][i] = (v0+2048)>>12;

143 samples[1][i] = (v1+2048)>>12;

144 }

145 } else if (out_ch == 1) {

146 for (i = 0; i < len; i++) {

147 v0 = 0;

148 for (j = 0; j < in_ch; j++)

149 v0 += samples[j][i] * matrix[0][j];

150 samples[0][i] = (v0+2048)>>12;

151 }

152 }

153 }

154

155 #include "eac3dec.c"

156 #include "ac3dec.c"

157

158 static const AVOption options[] = {

159 { "cons_noisegen", "enable consistent noise generation", OFFSET(consistent_noise_generation), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, PAR },

160 { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0, PAR },

161 { "heavy_compr", "enable heavy dynamic range compression", OFFSET(heavy_compression), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, PAR },

162 { "downmix", "Request a specific channel layout from the decoder", OFFSET(downmix_layout), AV_OPT_TYPE_CHLAYOUT, {.str = NULL}, .flags = PAR },

163 { NULL},

164 };

165

166 static const AVClass ac3_decoder_class = {

167 .class_name = "Fixed-Point AC-3 Decoder",

168 .item_name = av_default_item_name,

169 .option = options,

170 .version = LIBAVUTIL_VERSION_INT,

171 };

172

173 const FFCodec ff_ac3_fixed_decoder = {

174 .p.name = "ac3_fixed",

175 CODEC_LONG_NAME("ATSC A/52A (AC-3)"),

176 .p.type = AVMEDIA_TYPE_AUDIO,

177 .p.id = AV_CODEC_ID_AC3,

178 .p.priv_class = &ac3_decoder_class,

179 .priv_data_size = sizeof (AC3DecodeContext),

180 .init = ac3_decode_init,

181 .close = ac3_decode_end,

182 FF_CODEC_DECODE_CB(ac3_decode_frame),

183 .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |

184 AV_CODEC_CAP_DR1,

185 .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,

186 AV_SAMPLE_FMT_NONE },

187 .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,

188 };

AV_CODEC_ID_AC3

@ AV_CODEC_ID_AC3

Definition: codec_id.h:443

FF_CODEC_CAP_INIT_CLEANUP

#define FF_CODEC_CAP_INIT_CLEANUP

The codec allows calling the close function for deallocation even if the init function returned a fai...

Definition: codec_internal.h:43

Definition: vc1dsp.c:43

ac3_decoder_class

static const AVClass ac3_decoder_class

Definition: ac3dec_fixed.c:166

AVOption.

Definition: opt.h:429

Definition: codec_internal.h:127

AVCodec p

The public AVCodec.

Definition: codec_internal.h:131

ac3_decode_frame

static int ac3_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame_ptr, AVPacket *avpkt)

Decode a single AC-3 frame.

Definition: ac3dec.c:1488

static void scale_coefs(int32_t *dst, const int32_t *src, int dynrng, int len)

Definition: ac3dec_fixed.c:62

FF_CODEC_DECODE_CB

#define FF_CODEC_DECODE_CB(func)

Definition: codec_internal.h:311

AVMEDIA_TYPE_AUDIO

@ AVMEDIA_TYPE_AUDIO

Definition: avutil.h:202

ac3_decode_init

static av_cold int ac3_decode_init(AVCodecContext *avctx)

AVCodec initialization.

Definition: ac3dec.c:207

CODEC_LONG_NAME

#define CODEC_LONG_NAME(str)

Definition: codec_internal.h:296

LIBAVUTIL_VERSION_INT

#define LIBAVUTIL_VERSION_INT

Definition: version.h:85

Describe the class of an AVClass context structure.

Definition: log.h:66

#define NULL

Definition: coverity.c:32

av_default_item_name

const char * av_default_item_name(void *ptr)

Return the context name.

Definition: log.c:237

AV_OPT_TYPE_CHLAYOUT

@ AV_OPT_TYPE_CHLAYOUT

Underlying C type is AVChannelLayout.

Definition: opt.h:331

AV_CODEC_CAP_CHANNEL_CONF

#define AV_CODEC_CAP_CHANNEL_CONF

Codec should fill in channel configuration and samplerate instead of container.

Definition: codec.h:106

int(* init)(AVBSFContext *ctx)

Definition: dts2pts.c:368

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

codec_internal.h

static int shift(int a, int b)

Definition: bonk.c:261

uint8_t ptrdiff_t const uint8_t ptrdiff_t int intptr_t intptr_t int int16_t * dst

Definition: dsp.h:83

AV_SAMPLE_FMT_NONE

@ AV_SAMPLE_FMT_NONE

Definition: samplefmt.h:56

end_freq_inv_tab

static const int end_freq_inv_tab[8]

Definition: ac3dec_fixed.c:57

AV_SAMPLE_FMT_S16P

@ AV_SAMPLE_FMT_S16P

signed 16 bits, planar

Definition: samplefmt.h:64

AV_OPT_TYPE_FLOAT

@ AV_OPT_TYPE_FLOAT

Underlying C type is float.

Definition: opt.h:271

i

#define i(width, name, range_min, range_max)

Definition: cbs_h2645.c:256

static av_always_inline av_const double round(double x)

Definition: libm.h:444

AVSampleFormat

Audio sample formats.

Definition: samplefmt.h:55

static av_cold int ac3_decode_end(AVCodecContext *avctx)

Uninitialize the AC-3 decoder.

Definition: ac3dec.c:1855

static const AVOption options[]

Definition: ac3dec_fixed.c:158

ac3_downmix_c_fixed16

static void ac3_downmix_c_fixed16(int16_t **samples, int16_t **matrix, int out_ch, int in_ch, int len)

Downmix samples from original signal to stereo or mono (this is for 16-bit samples and fixed point de...

Definition: ac3dec_fixed.c:130

const char * name

Name of the codec implementation.

Definition: codec.h:194

int len

Definition: vorbis_enc_data.h:426

AVClass::class_name

const char * class_name

The name of the class; usually it is the same name as the context structure type to which the AVClass...

Definition: log.h:71

it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option keep it simple and lowercase description are in without and describe what they for example set the foo of the bar offset is the offset of the field in your see the OFFSET() macro

static av_const int sign_extend(int val, unsigned bits)

Definition: mathops.h:131

else temp

Definition: vf_mcdeint.c:263

Filter the word "frame" indicates either a video frame or a group of audio samples

Definition: filter_design.txt:8

AV_OPT_TYPE_BOOL

@ AV_OPT_TYPE_BOOL

Underlying C type is int.

Definition: opt.h:327

int32_t

Definition: audioconvert.c:56

ff_ac3_fixed_decoder

const FFCodec ff_ac3_fixed_decoder

Definition: ac3dec_fixed.c:173

@ PAR

Definition: af_afade.c:60

#define src

Definition: vp8dsp.c:248

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