1 |
|
|
/* |
2 |
|
|
* LPCM codecs for PCM formats found in Video DVD streams |
3 |
|
|
* Copyright (c) 2013 Christian Schmidt |
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 |
|
|
* LPCM codecs for PCM formats found in Video DVD streams |
25 |
|
|
*/ |
26 |
|
|
|
27 |
|
|
#include "avcodec.h" |
28 |
|
|
#include "bytestream.h" |
29 |
|
|
#include "internal.h" |
30 |
|
|
|
31 |
|
|
typedef struct PCMDVDContext { |
32 |
|
|
uint32_t last_header; // Cached header to see if parsing is needed |
33 |
|
|
int block_size; // Size of a block of samples in bytes |
34 |
|
|
int last_block_size; // Size of the last block of samples in bytes |
35 |
|
|
int samples_per_block; // Number of samples per channel per block |
36 |
|
|
int groups_per_block; // Number of 20/24-bit sample groups per block |
37 |
|
|
int extra_sample_count; // Number of leftover samples in the buffer |
38 |
|
|
uint8_t extra_samples[8 * 3 * 4]; // Space for leftover samples from a frame |
39 |
|
|
// (8 channels, 3B/sample, 4 samples/block) |
40 |
|
|
} PCMDVDContext; |
41 |
|
|
|
42 |
|
4 |
static av_cold int pcm_dvd_decode_init(AVCodecContext *avctx) |
43 |
|
|
{ |
44 |
|
4 |
PCMDVDContext *s = avctx->priv_data; |
45 |
|
|
|
46 |
|
|
/* Invalid header to force parsing of the first header */ |
47 |
|
4 |
s->last_header = -1; |
48 |
|
|
|
49 |
|
4 |
return 0; |
50 |
|
|
} |
51 |
|
|
|
52 |
|
126 |
static int pcm_dvd_parse_header(AVCodecContext *avctx, const uint8_t *header) |
53 |
|
|
{ |
54 |
|
|
/* no traces of 44100 and 32000Hz in any commercial software or player */ |
55 |
|
|
static const uint32_t frequencies[4] = { 48000, 96000, 44100, 32000 }; |
56 |
|
126 |
PCMDVDContext *s = avctx->priv_data; |
57 |
|
126 |
int header_int = (header[0] & 0xe0) | (header[1] << 8) | (header[2] << 16); |
58 |
|
|
|
59 |
|
|
/* early exit if the header didn't change apart from the frame number */ |
60 |
✓✓ |
126 |
if (s->last_header == header_int) |
61 |
|
122 |
return 0; |
62 |
|
4 |
s->last_header = -1; |
63 |
|
|
|
64 |
✗✓ |
4 |
if (avctx->debug & FF_DEBUG_PICT_INFO) |
65 |
|
|
av_log(avctx, AV_LOG_DEBUG, "pcm_dvd_parse_header: header = %02x%02x%02x\n", |
66 |
|
|
header[0], header[1], header[2]); |
67 |
|
|
/* |
68 |
|
|
* header[0] emphasis (1), muse(1), reserved(1), frame number(5) |
69 |
|
|
* header[1] quant (2), freq(2), reserved(1), channels(3) |
70 |
|
|
* header[2] dynamic range control (0x80 = off) |
71 |
|
|
*/ |
72 |
|
|
|
73 |
|
|
/* Discard potentially existing leftover samples from old channel layout */ |
74 |
|
4 |
s->extra_sample_count = 0; |
75 |
|
|
|
76 |
|
|
/* get the sample depth and derive the sample format from it */ |
77 |
|
4 |
avctx->bits_per_coded_sample = 16 + (header[1] >> 6 & 3) * 4; |
78 |
✗✓ |
4 |
if (avctx->bits_per_coded_sample == 28) { |
79 |
|
|
av_log(avctx, AV_LOG_ERROR, |
80 |
|
|
"PCM DVD unsupported sample depth %i\n", |
81 |
|
|
avctx->bits_per_coded_sample); |
82 |
|
|
return AVERROR_INVALIDDATA; |
83 |
|
|
} |
84 |
|
8 |
avctx->sample_fmt = avctx->bits_per_coded_sample == 16 ? AV_SAMPLE_FMT_S16 |
85 |
✓✓ |
4 |
: AV_SAMPLE_FMT_S32; |
86 |
|
4 |
avctx->bits_per_raw_sample = avctx->bits_per_coded_sample; |
87 |
|
|
|
88 |
|
|
/* get the sample rate */ |
89 |
|
4 |
avctx->sample_rate = frequencies[header[1] >> 4 & 3]; |
90 |
|
|
|
91 |
|
|
/* get the number of channels */ |
92 |
|
4 |
avctx->channels = 1 + (header[1] & 7); |
93 |
|
|
/* calculate the bitrate */ |
94 |
|
4 |
avctx->bit_rate = avctx->channels * |
95 |
|
4 |
avctx->sample_rate * |
96 |
|
4 |
avctx->bits_per_coded_sample; |
97 |
|
|
|
98 |
|
|
/* 4 samples form a group in 20/24-bit PCM on DVD Video. |
99 |
|
|
* A block is formed by the number of groups that are |
100 |
|
|
* needed to complete a set of samples for each channel. */ |
101 |
✓✓ |
4 |
if (avctx->bits_per_coded_sample == 16) { |
102 |
|
2 |
s->samples_per_block = 1; |
103 |
|
2 |
s->block_size = avctx->channels * 2; |
104 |
|
|
} else { |
105 |
✓✗✗ |
2 |
switch (avctx->channels) { |
106 |
|
2 |
case 1: |
107 |
|
|
case 2: |
108 |
|
|
case 4: |
109 |
|
|
/* one group has all the samples needed */ |
110 |
|
2 |
s->block_size = 4 * avctx->bits_per_coded_sample / 8; |
111 |
|
2 |
s->samples_per_block = 4 / avctx->channels; |
112 |
|
2 |
s->groups_per_block = 1; |
113 |
|
2 |
break; |
114 |
|
|
case 8: |
115 |
|
|
/* two groups have all the samples needed */ |
116 |
|
|
s->block_size = 8 * avctx->bits_per_coded_sample / 8; |
117 |
|
|
s->samples_per_block = 1; |
118 |
|
|
s->groups_per_block = 2; |
119 |
|
|
break; |
120 |
|
|
default: |
121 |
|
|
/* need avctx->channels groups */ |
122 |
|
|
s->block_size = 4 * avctx->channels * |
123 |
|
|
avctx->bits_per_coded_sample / 8; |
124 |
|
|
s->samples_per_block = 4; |
125 |
|
|
s->groups_per_block = avctx->channels; |
126 |
|
|
break; |
127 |
|
|
} |
128 |
|
|
} |
129 |
|
|
|
130 |
|
4 |
if (avctx->debug & FF_DEBUG_PICT_INFO) |
131 |
|
|
ff_dlog(avctx, |
132 |
|
|
"pcm_dvd_parse_header: %d channels, %d bits per sample, %d Hz, %"PRId64" bit/s\n", |
133 |
|
|
avctx->channels, avctx->bits_per_coded_sample, |
134 |
|
|
avctx->sample_rate, avctx->bit_rate); |
135 |
|
|
|
136 |
|
4 |
s->last_header = header_int; |
137 |
|
|
|
138 |
|
4 |
return 0; |
139 |
|
|
} |
140 |
|
|
|
141 |
|
126 |
static void *pcm_dvd_decode_samples(AVCodecContext *avctx, const uint8_t *src, |
142 |
|
|
void *dst, int blocks) |
143 |
|
|
{ |
144 |
|
126 |
PCMDVDContext *s = avctx->priv_data; |
145 |
|
126 |
int16_t *dst16 = dst; |
146 |
|
126 |
int32_t *dst32 = dst; |
147 |
|
|
GetByteContext gb; |
148 |
|
|
int i; |
149 |
|
|
uint8_t t; |
150 |
|
|
|
151 |
|
126 |
bytestream2_init(&gb, src, blocks * s->block_size); |
152 |
✓✗✓✗
|
126 |
switch (avctx->bits_per_coded_sample) { |
153 |
|
2 |
case 16: { |
154 |
|
|
#if HAVE_BIGENDIAN |
155 |
|
|
bytestream2_get_buffer(&gb, dst16, blocks * s->block_size); |
156 |
|
|
dst16 += blocks * s->block_size / 2; |
157 |
|
|
#else |
158 |
|
2 |
int samples = blocks * avctx->channels; |
159 |
|
|
do { |
160 |
|
2002 |
*dst16++ = bytestream2_get_be16u(&gb); |
161 |
✓✓ |
2002 |
} while (--samples); |
162 |
|
|
#endif |
163 |
|
2 |
return dst16; |
164 |
|
|
} |
165 |
|
|
case 20: |
166 |
|
|
if (avctx->channels == 1) { |
167 |
|
|
do { |
168 |
|
|
for (i = 2; i; i--) { |
169 |
|
|
dst32[0] = bytestream2_get_be16u(&gb) << 16; |
170 |
|
|
dst32[1] = bytestream2_get_be16u(&gb) << 16; |
171 |
|
|
t = bytestream2_get_byteu(&gb); |
172 |
|
|
*dst32++ += (t & 0xf0) << 8; |
173 |
|
|
*dst32++ += (t & 0x0f) << 12; |
174 |
|
|
} |
175 |
|
|
} while (--blocks); |
176 |
|
|
} else { |
177 |
|
|
do { |
178 |
|
|
for (i = s->groups_per_block; i; i--) { |
179 |
|
|
dst32[0] = bytestream2_get_be16u(&gb) << 16; |
180 |
|
|
dst32[1] = bytestream2_get_be16u(&gb) << 16; |
181 |
|
|
dst32[2] = bytestream2_get_be16u(&gb) << 16; |
182 |
|
|
dst32[3] = bytestream2_get_be16u(&gb) << 16; |
183 |
|
|
t = bytestream2_get_byteu(&gb); |
184 |
|
|
*dst32++ += (t & 0xf0) << 8; |
185 |
|
|
*dst32++ += (t & 0x0f) << 12; |
186 |
|
|
t = bytestream2_get_byteu(&gb); |
187 |
|
|
*dst32++ += (t & 0xf0) << 8; |
188 |
|
|
*dst32++ += (t & 0x0f) << 12; |
189 |
|
|
} |
190 |
|
|
} while (--blocks); |
191 |
|
|
} |
192 |
|
|
return dst32; |
193 |
|
124 |
case 24: |
194 |
✗✓ |
124 |
if (avctx->channels == 1) { |
195 |
|
|
do { |
196 |
|
|
for (i = 2; i; i--) { |
197 |
|
|
dst32[0] = bytestream2_get_be16u(&gb) << 16; |
198 |
|
|
dst32[1] = bytestream2_get_be16u(&gb) << 16; |
199 |
|
|
*dst32++ += bytestream2_get_byteu(&gb) << 8; |
200 |
|
|
*dst32++ += bytestream2_get_byteu(&gb) << 8; |
201 |
|
|
} |
202 |
|
|
} while (--blocks); |
203 |
|
|
} else { |
204 |
|
|
do { |
205 |
✓✓ |
41416 |
for (i = s->groups_per_block; i; i--) { |
206 |
|
20708 |
dst32[0] = bytestream2_get_be16u(&gb) << 16; |
207 |
|
20708 |
dst32[1] = bytestream2_get_be16u(&gb) << 16; |
208 |
|
20708 |
dst32[2] = bytestream2_get_be16u(&gb) << 16; |
209 |
|
20708 |
dst32[3] = bytestream2_get_be16u(&gb) << 16; |
210 |
|
20708 |
*dst32++ += bytestream2_get_byteu(&gb) << 8; |
211 |
|
20708 |
*dst32++ += bytestream2_get_byteu(&gb) << 8; |
212 |
|
20708 |
*dst32++ += bytestream2_get_byteu(&gb) << 8; |
213 |
|
20708 |
*dst32++ += bytestream2_get_byteu(&gb) << 8; |
214 |
|
|
} |
215 |
✓✓ |
20708 |
} while (--blocks); |
216 |
|
|
} |
217 |
|
124 |
return dst32; |
218 |
|
|
default: |
219 |
|
|
return NULL; |
220 |
|
|
} |
221 |
|
|
} |
222 |
|
|
|
223 |
|
126 |
static int pcm_dvd_decode_frame(AVCodecContext *avctx, void *data, |
224 |
|
|
int *got_frame_ptr, AVPacket *avpkt) |
225 |
|
|
{ |
226 |
|
126 |
AVFrame *frame = data; |
227 |
|
126 |
const uint8_t *src = avpkt->data; |
228 |
|
126 |
int buf_size = avpkt->size; |
229 |
|
126 |
PCMDVDContext *s = avctx->priv_data; |
230 |
|
|
int retval; |
231 |
|
|
int blocks; |
232 |
|
|
void *dst; |
233 |
|
|
|
234 |
✗✓ |
126 |
if (buf_size < 3) { |
235 |
|
|
av_log(avctx, AV_LOG_ERROR, "PCM packet too small\n"); |
236 |
|
|
return AVERROR_INVALIDDATA; |
237 |
|
|
} |
238 |
|
|
|
239 |
✗✓ |
126 |
if ((retval = pcm_dvd_parse_header(avctx, src))) |
240 |
|
|
return retval; |
241 |
✓✓✗✓
|
126 |
if (s->last_block_size && s->last_block_size != s->block_size) { |
242 |
|
|
av_log(avctx, AV_LOG_WARNING, "block_size has changed %d != %d\n", s->last_block_size, s->block_size); |
243 |
|
|
s->extra_sample_count = 0; |
244 |
|
|
} |
245 |
|
126 |
s->last_block_size = s->block_size; |
246 |
|
126 |
src += 3; |
247 |
|
126 |
buf_size -= 3; |
248 |
|
|
|
249 |
|
126 |
blocks = (buf_size + s->extra_sample_count) / s->block_size; |
250 |
|
|
|
251 |
|
|
/* get output buffer */ |
252 |
|
126 |
frame->nb_samples = blocks * s->samples_per_block; |
253 |
✗✓ |
126 |
if ((retval = ff_get_buffer(avctx, frame, 0)) < 0) |
254 |
|
|
return retval; |
255 |
|
126 |
dst = frame->data[0]; |
256 |
|
|
|
257 |
|
|
/* consume leftover samples from last packet */ |
258 |
✗✓ |
126 |
if (s->extra_sample_count) { |
259 |
|
|
int missing_samples = s->block_size - s->extra_sample_count; |
260 |
|
|
if (buf_size >= missing_samples) { |
261 |
|
|
memcpy(s->extra_samples + s->extra_sample_count, src, |
262 |
|
|
missing_samples); |
263 |
|
|
dst = pcm_dvd_decode_samples(avctx, s->extra_samples, dst, 1); |
264 |
|
|
src += missing_samples; |
265 |
|
|
buf_size -= missing_samples; |
266 |
|
|
s->extra_sample_count = 0; |
267 |
|
|
blocks--; |
268 |
|
|
} else { |
269 |
|
|
/* new packet still doesn't have enough samples */ |
270 |
|
|
memcpy(s->extra_samples + s->extra_sample_count, src, buf_size); |
271 |
|
|
s->extra_sample_count += buf_size; |
272 |
|
|
return avpkt->size; |
273 |
|
|
} |
274 |
|
|
} |
275 |
|
|
|
276 |
|
|
/* decode remaining complete samples */ |
277 |
✓✗ |
126 |
if (blocks) { |
278 |
|
126 |
pcm_dvd_decode_samples(avctx, src, dst, blocks); |
279 |
|
126 |
buf_size -= blocks * s->block_size; |
280 |
|
|
} |
281 |
|
|
|
282 |
|
|
/* store leftover samples */ |
283 |
✗✓ |
126 |
if (buf_size) { |
284 |
|
|
src += blocks * s->block_size; |
285 |
|
|
memcpy(s->extra_samples, src, buf_size); |
286 |
|
|
s->extra_sample_count = buf_size; |
287 |
|
|
} |
288 |
|
|
|
289 |
|
126 |
*got_frame_ptr = 1; |
290 |
|
|
|
291 |
|
126 |
return avpkt->size; |
292 |
|
|
} |
293 |
|
|
|
294 |
|
|
AVCodec ff_pcm_dvd_decoder = { |
295 |
|
|
.name = "pcm_dvd", |
296 |
|
|
.long_name = NULL_IF_CONFIG_SMALL("PCM signed 16|20|24-bit big-endian for DVD media"), |
297 |
|
|
.type = AVMEDIA_TYPE_AUDIO, |
298 |
|
|
.id = AV_CODEC_ID_PCM_DVD, |
299 |
|
|
.priv_data_size = sizeof(PCMDVDContext), |
300 |
|
|
.init = pcm_dvd_decode_init, |
301 |
|
|
.decode = pcm_dvd_decode_frame, |
302 |
|
|
.capabilities = AV_CODEC_CAP_CHANNEL_CONF | |
303 |
|
|
AV_CODEC_CAP_DR1, |
304 |
|
|
.sample_fmts = (const enum AVSampleFormat[]) { |
305 |
|
|
AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_NONE |
306 |
|
|
}, |
307 |
|
|
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, |
308 |
|
|
}; |