FFmpeg
vima.c
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1 /*
2  * LucasArts VIMA decoder
3  * Copyright (c) 2012 Paul B Mahol
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  * LucasArts VIMA audio decoder
25  * @author Paul B Mahol
26  */
27 
29 #include "libavutil/thread.h"
30 
31 #include "adpcm_data.h"
32 #include "avcodec.h"
33 #include "codec_internal.h"
34 #include "decode.h"
35 #include "get_bits.h"
36 
37 static uint16_t predict_table[5786 * 2];
38 
39 static const uint8_t size_table[] = {
40  4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
41  4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
42  4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
43  5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
44  6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
45  7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7
46 };
47 
48 static const int8_t index_table1[] = {
49  -1, 4, -1, 4
50 };
51 
52 static const int8_t index_table2[] = {
53  -1, -1, 2, 6, -1, -1, 2, 6
54 };
55 
56 static const int8_t index_table3[] = {
57  -1, -1, -1, -1, 1, 2, 4, 6, -1, -1, -1, -1, 1, 2, 4, 6
58 };
59 
60 static const int8_t index_table4[] = {
61  -1, -1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 2, 2, 4, 5, 6,
62  -1, -1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 2, 2, 4, 5, 6
63 };
64 
65 static const int8_t index_table5[] = {
66  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
67  1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 5, 5, 6, 6,
68  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
69  1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 5, 5, 6, 6
70 };
71 
72 static const int8_t index_table6[] = {
73  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
74  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
75  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2,
76  2, 2, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6,
77  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
78  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
79  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2,
80  2, 2, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6
81 };
82 
83 static const int8_t *const step_index_tables[] = {
86 };
87 
88 static av_cold void predict_table_init(void)
89 {
90  for (int start_pos = 0; start_pos < 64; start_pos++) {
91  unsigned int dest_pos, table_pos;
92 
93  for (table_pos = 0, dest_pos = start_pos;
95  table_pos++, dest_pos += 64) {
96  int put = 0, count, table_value;
97 
98  table_value = ff_adpcm_step_table[table_pos];
99  for (count = 32; count != 0; count >>= 1) {
100  if (start_pos & count)
101  put += table_value;
102  table_value >>= 1;
103  }
104  predict_table[dest_pos] = put;
105  }
106  }
107 }
108 
110 {
111  static AVOnce init_static_once = AV_ONCE_INIT;
112 
113  avctx->sample_fmt = AV_SAMPLE_FMT_S16;
114 
115  ff_thread_once(&init_static_once, predict_table_init);
116 
117  return 0;
118 }
119 
121  int *got_frame_ptr, AVPacket *pkt)
122 {
123  GetBitContext gb;
124  int16_t pcm_data[2];
125  uint32_t samples;
126  int8_t channel_hint[2];
127  int ret, chan;
128  int channels = 1;
129 
130  if (pkt->size < 13)
131  return AVERROR_INVALIDDATA;
132 
133  if ((ret = init_get_bits8(&gb, pkt->data, pkt->size)) < 0)
134  return ret;
135 
136  samples = get_bits_long(&gb, 32);
137  if (samples == 0xffffffff) {
138  skip_bits_long(&gb, 32);
139  samples = get_bits_long(&gb, 32);
140  }
141 
142  if (samples > pkt->size * 2)
143  return AVERROR_INVALIDDATA;
144 
145  channel_hint[0] = get_sbits(&gb, 8);
146  if (channel_hint[0] & 0x80) {
147  channel_hint[0] = ~channel_hint[0];
148  channels = 2;
149  }
152  pcm_data[0] = get_sbits(&gb, 16);
153  if (channels > 1) {
154  channel_hint[1] = get_sbits(&gb, 8);
155  pcm_data[1] = get_sbits(&gb, 16);
156  }
157 
159  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
160  return ret;
161 
162  for (chan = 0; chan < channels; chan++) {
163  uint16_t *dest = (uint16_t *)frame->data[0] + chan;
164  int step_index = channel_hint[chan];
165  int output = pcm_data[chan];
166  int sample;
167 
168  for (sample = 0; sample < samples; sample++) {
169  int lookup_size, lookup, highbit, lowbits;
170 
171  step_index = av_clip(step_index, 0, 88);
172  lookup_size = size_table[step_index];
173  lookup = get_bits(&gb, lookup_size);
174  highbit = 1 << (lookup_size - 1);
175  lowbits = highbit - 1;
176 
177  if (lookup & highbit)
178  lookup ^= highbit;
179  else
180  highbit = 0;
181 
182  if (lookup == lowbits) {
183  output = get_sbits(&gb, 16);
184  } else {
185  int predict_index, diff;
186 
187  predict_index = (lookup << (7 - lookup_size)) | (step_index << 6);
188  predict_index = av_clip(predict_index, 0, 5785);
189  diff = predict_table[predict_index];
190  if (lookup)
191  diff += ff_adpcm_step_table[step_index] >> (lookup_size - 1);
192  if (highbit)
193  diff = -diff;
194 
196  }
197 
198  *dest = output;
199  dest += channels;
200 
201  step_index += step_index_tables[lookup_size - 2][lookup];
202  }
203  }
204 
205  *got_frame_ptr = 1;
206 
207  return pkt->size;
208 }
209 
211  .p.name = "adpcm_vima",
212  CODEC_LONG_NAME("LucasArts VIMA audio"),
213  .p.type = AVMEDIA_TYPE_AUDIO,
214  .p.id = AV_CODEC_ID_ADPCM_VIMA,
215  .init = decode_init,
217  .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
218 };
skip_bits_long
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:278
av_clip
#define av_clip
Definition: common.h:98
thread.h
get_bits_long
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:421
output
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce output
Definition: filter_design.txt:225
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:522
FFCodec
Definition: codec_internal.h:127
index_table2
static const int8_t index_table2[]
Definition: vima.c:52
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:335
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:2111
index_table4
static const int8_t index_table4[]
Definition: vima.c:60
GetBitContext
Definition: get_bits.h:108
ff_thread_once
static int ff_thread_once(char *control, void(*routine)(void))
Definition: thread.h:205
pkt
AVPacket * pkt
Definition: movenc.c:59
FF_ARRAY_ELEMS
#define FF_ARRAY_ELEMS(a)
Definition: sinewin_tablegen.c:29
av_cold
#define av_cold
Definition: attributes.h:90
init_get_bits8
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:545
decode_frame
static int decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame_ptr, AVPacket *pkt)
Definition: vima.c:120
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:306
adpcm_data.h
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
get_sbits
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:320
channels
channels
Definition: aptx.h:31
decode.h
get_bits.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
frame
static AVFrame * frame
Definition: demux_decode.c:54
index_table5
static const int8_t index_table5[]
Definition: vima.c:65
ff_adpcm_vima_decoder
const FFCodec ff_adpcm_vima_decoder
Definition: vima.c:210
AV_ONCE_INIT
#define AV_ONCE_INIT
Definition: thread.h:203
av_clip_int16
#define av_clip_int16
Definition: common.h:113
index_table1
static const int8_t index_table1[]
Definition: vima.c:48
predict_table_init
static av_cold void predict_table_init(void)
Definition: vima.c:88
AV_CODEC_ID_ADPCM_VIMA
@ AV_CODEC_ID_ADPCM_VIMA
Definition: codec_id.h:400
AVOnce
#define AVOnce
Definition: thread.h:202
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
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1618
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
AVPacket::size
int size
Definition: packet.h:523
codec_internal.h
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
ff_adpcm_step_table
const int16_t ff_adpcm_step_table[89]
This is the step table.
Definition: adpcm_data.c:39
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1084
sample
#define sample
Definition: flacdsp_template.c:44
diff
static av_always_inline int diff(const struct color_info *a, const struct color_info *b, const int trans_thresh)
Definition: vf_paletteuse.c:164
av_channel_layout_default
void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels)
Get the default channel layout for a given number of channels.
Definition: channel_layout.c:1033
index_table6
static const int8_t index_table6[]
Definition: vima.c:72
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:420
lookup
int lookup
Definition: vorbis_enc_data.h:428
step_index_tables
static const int8_t *const step_index_tables[]
Definition: vima.c:83
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
avcodec.h
ret
ret
Definition: filter_design.txt:187
predict_table
static uint16_t predict_table[5786 *2]
Definition: vima.c:37
AVCodecContext
main external API structure.
Definition: avcodec.h:445
channel_layout.h
av_channel_layout_uninit
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
Free any allocated data in the channel layout and reset the channel count to 0.
Definition: channel_layout.c:662
index_table3
static const int8_t index_table3[]
Definition: vima.c:56
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
size_table
static const uint8_t size_table[]
Definition: vima.c:39
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: vima.c:109