FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavcodec/g722dec.c
Date: 2024-11-20 23:03:26
Exec Total Coverage
Lines: 39 41 95.1%
Functions: 2 2 100.0%
Branches: 6 8 75.0%
Line Branch Exec Source
1 /*
2 * Copyright (c) CMU 1993 Computer Science, Speech Group
3 * Chengxiang Lu and Alex Hauptmann
4 * Copyright (c) 2005 Steve Underwood <steveu at coppice.org>
5 * Copyright (c) 2009 Kenan Gillet
6 * Copyright (c) 2010 Martin Storsjo
7 *
8 * This file is part of FFmpeg.
9 *
10 * FFmpeg is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
14 *
15 * FFmpeg is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 */
24
25 /**
26 * @file
27 * G.722 ADPCM audio decoder
28 *
29 * This G.722 decoder is a bit-exact implementation of the ITU G.722
30 * specification for all three specified bitrates - 64000bps, 56000bps
31 * and 48000bps. It passes the ITU tests.
32 *
33 * @note For the 56000bps and 48000bps bitrates, the lowest 1 or 2 bits
34 * respectively of each byte are ignored.
35 */
36
37 #include "libavutil/channel_layout.h"
38 #include "libavutil/opt.h"
39 #include "avcodec.h"
40 #include "codec_internal.h"
41 #include "decode.h"
42 #include "get_bits.h"
43 #include "g722.h"
44
45 #define OFFSET(x) offsetof(G722Context, x)
46 #define AD AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_DECODING_PARAM
47 static const AVOption options[] = {
48 { "bits_per_codeword", "Bits per G722 codeword", OFFSET(bits_per_codeword), AV_OPT_TYPE_INT, { .i64 = 8 }, 6, 8, AD },
49 { NULL }
50 };
51
52 static const AVClass g722_decoder_class = {
53 .class_name = "g722 decoder",
54 .item_name = av_default_item_name,
55 .option = options,
56 .version = LIBAVUTIL_VERSION_INT,
57 };
58
59 4 static av_cold int g722_decode_init(AVCodecContext * avctx)
60 {
61 4 G722Context *c = avctx->priv_data;
62
63 4 av_channel_layout_uninit(&avctx->ch_layout);
64 4 avctx->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
65 4 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
66
67 4 c->band[0].scale_factor = 8;
68 4 c->band[1].scale_factor = 2;
69 4 c->prev_samples_pos = 22;
70
71 4 ff_g722dsp_init(&c->dsp);
72
73 4 return 0;
74 }
75
76 static const int16_t low_inv_quant5[32] = {
77 -35, -35, -2919, -2195, -1765, -1458, -1219, -1023,
78 -858, -714, -587, -473, -370, -276, -190, -110,
79 2919, 2195, 1765, 1458, 1219, 1023, 858, 714,
80 587, 473, 370, 276, 190, 110, 35, -35
81 };
82
83 static const int16_t * const low_inv_quants[3] = { ff_g722_low_inv_quant6,
84 low_inv_quant5,
85 ff_g722_low_inv_quant4 };
86
87 263 static int g722_decode_frame(AVCodecContext *avctx, AVFrame *frame,
88 int *got_frame_ptr, AVPacket *avpkt)
89 {
90 263 G722Context *c = avctx->priv_data;
91 int16_t *out_buf;
92 int j, ret;
93 263 const int skip = 8 - c->bits_per_codeword;
94 263 const int16_t *quantizer_table = low_inv_quants[skip];
95 GetBitContext gb;
96
97 /* get output buffer */
98 263 frame->nb_samples = avpkt->size * 2;
99
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 263 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
100 ✗ return ret;
101 263 out_buf = (int16_t *)frame->data[0];
102
103 263 ret = init_get_bits8(&gb, avpkt->data, avpkt->size);
104
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 263 if (ret < 0)
105 ✗ return ret;
106
107
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 220125 for (j = 0; j < avpkt->size; j++) {
108 int ilow, ihigh, rlow, rhigh, dhigh;
109 int xout[2];
110
111 219862 ihigh = get_bits(&gb, 2);
112 219862 ilow = get_bits(&gb, 6 - skip);
113 219862 skip_bits(&gb, skip);
114
115 219862 rlow = av_clip_intp2((c->band[0].scale_factor * quantizer_table[ilow] >> 10)
116 219862 + c->band[0].s_predictor, 14);
117
118 219862 ff_g722_update_low_predictor(&c->band[0], ilow >> (2 - skip));
119
120 219862 dhigh = c->band[1].scale_factor * ff_g722_high_inv_quant[ihigh] >> 10;
121 219862 rhigh = av_clip_intp2(dhigh + c->band[1].s_predictor, 14);
122
123 219862 ff_g722_update_high_predictor(&c->band[1], dhigh, ihigh);
124
125 219862 c->prev_samples[c->prev_samples_pos++] = rlow + rhigh;
126 219862 c->prev_samples[c->prev_samples_pos++] = rlow - rhigh;
127 219862 c->dsp.apply_qmf(c->prev_samples + c->prev_samples_pos - 24, xout);
128 219862 *out_buf++ = av_clip_int16(xout[0] >> 11);
129 219862 *out_buf++ = av_clip_int16(xout[1] >> 11);
130
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 219862 if (c->prev_samples_pos >= PREV_SAMPLES_BUF_SIZE) {
131 437 memmove(c->prev_samples, c->prev_samples + c->prev_samples_pos - 22,
132 22 * sizeof(c->prev_samples[0]));
133 437 c->prev_samples_pos = 22;
134 }
135 }
136
137 263 *got_frame_ptr = 1;
138
139 263 return avpkt->size;
140 }
141
142 const FFCodec ff_adpcm_g722_decoder = {
143 .p.name = "g722",
144 CODEC_LONG_NAME("G.722 ADPCM"),
145 .p.type = AVMEDIA_TYPE_AUDIO,
146 .p.id = AV_CODEC_ID_ADPCM_G722,
147 .priv_data_size = sizeof(G722Context),
148 .init = g722_decode_init,
149 FF_CODEC_DECODE_CB(g722_decode_frame),
150 .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
151 .p.priv_class = &g722_decoder_class,
152 };
153