Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / pcm-dvd.c
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 20/24bit sample groups per block
37 uint8_t *extra_samples; // Pointer to leftover samples from a frame
38 int extra_sample_count; // Number of leftover samples in the buffer
39 } PCMDVDContext;
40
41 static av_cold int pcm_dvd_decode_init(AVCodecContext *avctx)
42 {
43 PCMDVDContext *s = avctx->priv_data;
44
45 /* Invalid header to force parsing of the first header */
46 s->last_header = -1;
47 /* reserve space for 8 channels, 3 bytes/sample, 4 samples/block */
48 if (!(s->extra_samples = av_malloc(8 * 3 * 4)))
49 return AVERROR(ENOMEM);
50
51 return 0;
52 }
53
54 static av_cold int pcm_dvd_decode_uninit(AVCodecContext *avctx)
55 {
56 PCMDVDContext *s = avctx->priv_data;
57
58 av_freep(&s->extra_samples);
59
60 return 0;
61 }
62
63 static int pcm_dvd_parse_header(AVCodecContext *avctx, const uint8_t *header)
64 {
65 /* no traces of 44100 and 32000Hz in any commercial software or player */
66 static const uint32_t frequencies[4] = { 48000, 96000, 44100, 32000 };
67 PCMDVDContext *s = avctx->priv_data;
68 int header_int = (header[0] & 0xe0) | (header[1] << 8) | (header[2] << 16);
69
70 /* early exit if the header didn't change apart from the frame number */
71 if (s->last_header == header_int)
72 return 0;
73 s->last_header = -1;
74
75 if (avctx->debug & FF_DEBUG_PICT_INFO)
76 av_dlog(avctx, "pcm_dvd_parse_header: header = %02x%02x%02x\n",
77 header[0], header[1], header[2]);
78 /*
79 * header[0] emphasis (1), muse(1), reserved(1), frame number(5)
80 * header[1] quant (2), freq(2), reserved(1), channels(3)
81 * header[2] dynamic range control (0x80 = off)
82 */
83
84 /* Discard potentially existing leftover samples from old channel layout */
85 s->extra_sample_count = 0;
86
87 /* get the sample depth and derive the sample format from it */
88 avctx->bits_per_coded_sample = 16 + (header[1] >> 6 & 3) * 4;
89 if (avctx->bits_per_coded_sample == 28) {
90 av_log(avctx, AV_LOG_ERROR,
91 "PCM DVD unsupported sample depth %i\n",
92 avctx->bits_per_coded_sample);
93 return AVERROR_INVALIDDATA;
94 }
95 avctx->sample_fmt = avctx->bits_per_coded_sample == 16 ? AV_SAMPLE_FMT_S16
96 : AV_SAMPLE_FMT_S32;
97 avctx->bits_per_raw_sample = avctx->bits_per_coded_sample;
98
99 /* get the sample rate */
100 avctx->sample_rate = frequencies[header[1] >> 4 & 3];
101
102 /* get the number of channels */
103 avctx->channels = 1 + (header[1] & 7);
104 /* calculate the bitrate */
105 avctx->bit_rate = avctx->channels *
106 avctx->sample_rate *
107 avctx->bits_per_coded_sample;
108
109 /* 4 samples form a group in 20/24bit PCM on DVD Video.
110 * A block is formed by the number of groups that are
111 * needed to complete a set of samples for each channel. */
112 if (avctx->bits_per_coded_sample == 16) {
113 s->samples_per_block = 1;
114 s->block_size = avctx->channels * 2;
115 } else {
116 switch (avctx->channels) {
117 case 1:
118 case 2:
119 case 4:
120 /* one group has all the samples needed */
121 s->block_size = 4 * avctx->bits_per_coded_sample / 8;
122 s->samples_per_block = 4 / avctx->channels;
123 s->groups_per_block = 1;
124 break;
125 case 8:
126 /* two groups have all the samples needed */
127 s->block_size = 8 * avctx->bits_per_coded_sample / 8;
128 s->samples_per_block = 1;
129 s->groups_per_block = 2;
130 break;
131 default:
132 /* need avctx->channels groups */
133 s->block_size = 4 * avctx->channels *
134 avctx->bits_per_coded_sample / 8;
135 s->samples_per_block = 4;
136 s->groups_per_block = avctx->channels;
137 break;
138 }
139 }
140
141 if (avctx->debug & FF_DEBUG_PICT_INFO)
142 av_dlog(avctx,
143 "pcm_dvd_parse_header: %d channels, %d bits per sample, %d Hz, %d bit/s\n",
144 avctx->channels, avctx->bits_per_coded_sample,
145 avctx->sample_rate, avctx->bit_rate);
146
147 s->last_header = header_int;
148
149 return 0;
150 }
151
152 static void *pcm_dvd_decode_samples(AVCodecContext *avctx, const uint8_t *src,
153 void *dst, int blocks)
154 {
155 PCMDVDContext *s = avctx->priv_data;
156 int16_t *dst16 = dst;
157 int32_t *dst32 = dst;
158 GetByteContext gb;
159 int i;
160 uint8_t t;
161
162 bytestream2_init(&gb, src, blocks * s->block_size);
163 switch (avctx->bits_per_coded_sample) {
164 case 16: {
165 #if HAVE_BIGENDIAN
166 bytestream2_get_buffer(&gb, dst16, blocks * s->block_size);
167 dst16 += blocks * s->block_size / 2;
168 #else
169 int samples = blocks * avctx->channels;
170 do {
171 *dst16++ = bytestream2_get_be16u(&gb);
172 } while (--samples);
173 #endif
174 return dst16;
175 }
176 case 20:
177 if (avctx->channels == 1) {
178 do {
179 for (i = 2; i; i--) {
180 dst32[0] = bytestream2_get_be16u(&gb) << 16;
181 dst32[1] = bytestream2_get_be16u(&gb) << 16;
182 t = bytestream2_get_byteu(&gb);
183 *dst32++ += (t & 0xf0) << 8;
184 *dst32++ += (t & 0x0f) << 12;
185 }
186 } while (--blocks);
187 } else {
188 do {
189 for (i = s->groups_per_block; i; i--) {
190 dst32[0] = bytestream2_get_be16u(&gb) << 16;
191 dst32[1] = bytestream2_get_be16u(&gb) << 16;
192 dst32[2] = bytestream2_get_be16u(&gb) << 16;
193 dst32[3] = bytestream2_get_be16u(&gb) << 16;
194 t = bytestream2_get_byteu(&gb);
195 *dst32++ += (t & 0xf0) << 8;
196 *dst32++ += (t & 0x0f) << 12;
197 t = bytestream2_get_byteu(&gb);
198 *dst32++ += (t & 0xf0) << 8;
199 *dst32++ += (t & 0x0f) << 12;
200 }
201 } while (--blocks);
202 }
203 return dst32;
204 case 24:
205 if (avctx->channels == 1) {
206 do {
207 for (i = 2; i; i--) {
208 dst32[0] = bytestream2_get_be16u(&gb) << 16;
209 dst32[1] = bytestream2_get_be16u(&gb) << 16;
210 *dst32++ += bytestream2_get_byteu(&gb) << 8;
211 *dst32++ += bytestream2_get_byteu(&gb) << 8;
212 }
213 } while (--blocks);
214 } else {
215 do {
216 for (i = s->groups_per_block; i; i--) {
217 dst32[0] = bytestream2_get_be16u(&gb) << 16;
218 dst32[1] = bytestream2_get_be16u(&gb) << 16;
219 dst32[2] = bytestream2_get_be16u(&gb) << 16;
220 dst32[3] = bytestream2_get_be16u(&gb) << 16;
221 *dst32++ += bytestream2_get_byteu(&gb) << 8;
222 *dst32++ += bytestream2_get_byteu(&gb) << 8;
223 *dst32++ += bytestream2_get_byteu(&gb) << 8;
224 *dst32++ += bytestream2_get_byteu(&gb) << 8;
225 }
226 } while (--blocks);
227 }
228 return dst32;
229 default:
230 return NULL;
231 }
232 }
233
234 static int pcm_dvd_decode_frame(AVCodecContext *avctx, void *data,
235 int *got_frame_ptr, AVPacket *avpkt)
236 {
237 AVFrame *frame = data;
238 const uint8_t *src = avpkt->data;
239 int buf_size = avpkt->size;
240 PCMDVDContext *s = avctx->priv_data;
241 int retval;
242 int blocks;
243 void *dst;
244
245 if (buf_size < 3) {
246 av_log(avctx, AV_LOG_ERROR, "PCM packet too small\n");
247 return AVERROR_INVALIDDATA;
248 }
249
250 if ((retval = pcm_dvd_parse_header(avctx, src)))
251 return retval;
252 if (s->last_block_size && s->last_block_size != s->block_size) {
253 av_log(avctx, AV_LOG_WARNING, "block_size has changed %d != %d\n", s->last_block_size, s->block_size);
254 s->extra_sample_count = 0;
255 }
256 s->last_block_size = s->block_size;
257 src += 3;
258 buf_size -= 3;
259
260 blocks = (buf_size + s->extra_sample_count) / s->block_size;
261
262 /* get output buffer */
263 frame->nb_samples = blocks * s->samples_per_block;
264 if ((retval = ff_get_buffer(avctx, frame, 0)) < 0)
265 return retval;
266 dst = frame->data[0];
267
268 /* consume leftover samples from last packet */
269 if (s->extra_sample_count) {
270 int missing_samples = s->block_size - s->extra_sample_count;
271 if (buf_size >= missing_samples) {
272 memcpy(s->extra_samples + s->extra_sample_count, src,
273 missing_samples);
274 dst = pcm_dvd_decode_samples(avctx, s->extra_samples, dst, 1);
275 src += missing_samples;
276 buf_size -= missing_samples;
277 s->extra_sample_count = 0;
278 blocks--;
279 } else {
280 /* new packet still doesn't have enough samples */
281 memcpy(s->extra_samples + s->extra_sample_count, src, buf_size);
282 s->extra_sample_count += buf_size;
283 return avpkt->size;
284 }
285 }
286
287 /* decode remaining complete samples */
288 if (blocks) {
289 pcm_dvd_decode_samples(avctx, src, dst, blocks);
290 buf_size -= blocks * s->block_size;
291 }
292
293 /* store leftover samples */
294 if (buf_size) {
295 src += blocks * s->block_size;
296 memcpy(s->extra_samples, src, buf_size);
297 s->extra_sample_count = buf_size;
298 }
299
300 *got_frame_ptr = 1;
301
302 return avpkt->size;
303 }
304
305 AVCodec ff_pcm_dvd_decoder = {
306 .name = "pcm_dvd",
307 .long_name = NULL_IF_CONFIG_SMALL("PCM signed 16|20|24-bit big-endian for DVD media"),
308 .type = AVMEDIA_TYPE_AUDIO,
309 .id = AV_CODEC_ID_PCM_DVD,
310 .priv_data_size = sizeof(PCMDVDContext),
311 .init = pcm_dvd_decode_init,
312 .decode = pcm_dvd_decode_frame,
313 .close = pcm_dvd_decode_uninit,
314 .capabilities = CODEC_CAP_DR1,
315 .sample_fmts = (const enum AVSampleFormat[]) {
316 AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_NONE
317 }
318 };