FFmpeg: libavcodec/vima.c Source File

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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 
28 #include "libavutil/channel_layout.h"
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[] = {
84  index_table1, index_table2, index_table3,
85  index_table4, index_table5, index_table6
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;
94  table_pos < FF_ARRAY_ELEMS(ff_adpcm_step_table);
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 
109  static av_cold int decode_init(AVCodecContext *avctx)
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 
120  static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
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  }
150  av_channel_layout_uninit(&avctx->ch_layout);
151  av_channel_layout_default(&avctx->ch_layout, channels);
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 
158  frame->nb_samples = samples;
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 
195  output = av_clip_int16(output + diff);
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 
210  const FFCodec ff_adpcm_vima_decoder = {
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,
216  FF_CODEC_DECODE_CB(decode_frame),
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:100
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:389
AVPacket::data
uint8_t * data
Definition: packet.h:539
FFCodec
Definition: codec_internal.h:127
index_table2
static const int8_t index_table2[]
Definition: vima.c:52
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:1071
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:60
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:311
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:296
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:115
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:397
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:1719
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:540
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:1063
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:834
index_table6
static const int8_t index_table6[]
Definition: vima.c:72
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
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
predict_table
static uint16_t predict_table[5786 *2]
Definition: vima.c:37
AVCodecContext
main external API structure.
Definition: avcodec.h:451
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:437
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:516
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
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