2 * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file mp3dec_filter.c Paraslash's mp3 decoder. */
14 #include "mp3dec_filter.cmdline.h"
18 #include "buffer_tree.h"
23 /** Convert a sample value from libmad to a signed short. */
24 #define MAD_TO_SHORT(f) (f) >= MAD_F_ONE? SHRT_MAX :\
25 (f) <= -MAD_F_ONE? -SHRT_MAX : (signed short) ((f) >> (MAD_F_FRACBITS - 15))
27 /** State of the decoding process. */
29 /** Bad main_data_begin pointer encounterd. */
30 MP3DEC_FLAG_BAD_DATA = 1,
31 /** Some output has already been produced. */
32 MP3DEC_FLAG_DECODE_STARTED = 2,
33 MP3DEC_FLAG_NEED_MORE = 4,
36 /** Data specific to the mp3dec filter. */
37 struct private_mp3dec_data {
38 /** Information on the current mp3 stream. */
39 struct mad_stream stream;
40 /** Information about the frame which is currently decoded. */
41 struct mad_frame frame;
42 /** Contains the PCM output. */
43 struct mad_synth synth;
44 /** See \ref mp3dec_flags. */
46 /** Defer decoding until this time. */
47 struct timeval stream_start_barrier;
48 /** Wait until this many input bytes are available. */
49 size_t input_len_barrier;
50 /** The number of channels of the current stream. */
51 unsigned int channels;
52 /** Current sample rate in Hz. */
53 unsigned int samplerate;
56 static int need_bad_data_delay(struct private_mp3dec_data *pmd,
57 size_t bytes_available)
59 if (!(pmd->flags & MP3DEC_FLAG_BAD_DATA))
61 if (pmd->flags & MP3DEC_FLAG_DECODE_STARTED)
63 if (bytes_available >= pmd->input_len_barrier)
65 if (tv_diff(now, &pmd->stream_start_barrier, NULL) > 0)
71 * Returns negative on serious errors, zero if the error should be ignored and
72 * positive on bad data pointer errors at stream start.
74 static int handle_decode_error(struct private_mp3dec_data *pmd, size_t len)
76 const struct timeval delay = {0, 60 * 1000};
77 if (!MAD_RECOVERABLE(pmd->stream.error)
78 && pmd->stream.error != MAD_ERROR_BUFLEN) {
79 PARA_ERROR_LOG("%s\n", mad_stream_errorstr(&pmd->stream));
80 return -E_MAD_FRAME_DECODE;
82 PARA_DEBUG_LOG("%s\n", mad_stream_errorstr(&pmd->stream));
83 if (pmd->stream.error != MAD_ERROR_BADDATAPTR)
85 if (pmd->flags & MP3DEC_FLAG_DECODE_STARTED)
88 * Bad data pointer at stream start. Defer decoding until the amount of
89 * data we are about to skip is available again, but wait at most 60ms.
91 pmd->flags |= MP3DEC_FLAG_BAD_DATA;
92 pmd->input_len_barrier = len;
93 tv_add(now, &delay, &pmd->stream_start_barrier);
97 /** 640K ought to be enough for everybody ;) */
98 #define MP3DEC_MAX_PENDING (640 * 1024)
100 static void mp3dec_pre_select(struct sched *s, struct task *t)
102 struct filter_node *fn = container_of(t, struct filter_node, task);
103 size_t iqs = btr_get_input_queue_size(fn->btrn);
104 struct private_mp3dec_data *pmd = fn->private_data;
107 if (iqs <= pmd->input_len_barrier)
109 if (btr_bytes_pending(fn->btrn) > MP3DEC_MAX_PENDING)
110 return; /* FIXME, should use reasonable bound on timeout */
111 s->timeout.tv_sec = 0;
112 s->timeout.tv_usec = 1;
115 static ssize_t mp3dec(char *inbuffer, size_t len, struct filter_node *fn)
118 struct private_mp3dec_data *pmd = fn->private_data;
119 size_t copy = PARA_MIN(len, (size_t)4096);
121 if (fn->loaded + 16384 > fn->bufsize)
123 if (need_bad_data_delay(pmd, len))
125 mad_stream_buffer(&pmd->stream, (unsigned char *) inbuffer, copy);
126 pmd->stream.error = 0;
128 ret = mad_header_decode(&pmd->frame.header, &pmd->stream);
130 if (pmd->stream.error != MAD_ERROR_BUFLEN &&
131 pmd->stream.error != MAD_ERROR_LOSTSYNC)
132 PARA_DEBUG_LOG("header decode: %s\n",
133 mad_stream_errorstr(&pmd->stream));
136 fn->fc->samplerate = pmd->frame.header.samplerate;
137 fn->fc->channels = MAD_NCHANNELS(&pmd->frame.header);
138 ret = mad_frame_decode(&pmd->frame, &pmd->stream);
140 ret = handle_decode_error(pmd, len);
145 ret = copy - (pmd->stream.bufend - pmd->stream.next_frame);
146 PARA_NOTICE_LOG("skipping %d input bytes\n", ret);
149 mad_synth_frame(&pmd->synth, &pmd->frame);
150 pmd->flags |= MP3DEC_FLAG_DECODE_STARTED;
152 for (i = 0; i < pmd->synth.pcm.length; i++) {
153 int s = MAD_TO_SHORT(pmd->synth.pcm.samples[0][i]);
154 write_int16_host_endian(fn->buf + fn->loaded, s);
156 if (MAD_NCHANNELS(&pmd->frame.header) == 2) { /* stereo */
157 s = MAD_TO_SHORT(pmd->synth.pcm.samples[1][i]);
158 write_int16_host_endian(fn->buf + fn->loaded, s);
161 if (fn->loaded != fn->bufsize) /* output buffer not full */
163 PARA_ERROR_LOG("output buffer full: %zd\n", fn->loaded);
164 return -E_MP3DEC_OVERRUN;
166 if (fn->loaded + 16384 <= fn->bufsize)
169 if (pmd->stream.next_frame) { /* we still have some data */
170 size_t off = pmd->stream.bufend - pmd->stream.next_frame;
171 if (fn->loaded + 16384 <= fn->bufsize && off > 2048)
178 static size_t used_mad_buffer_bytes(struct mad_stream *s, size_t max)
184 /* we still have some data */
185 rv = s->next_frame - s->buffer;
190 static void mp3dec_close(struct filter_node *fn)
192 struct private_mp3dec_data *pmd = fn->private_data;
194 mad_synth_finish(&pmd->synth);
195 mad_frame_finish(&pmd->frame);
196 mad_stream_finish(&pmd->stream);
201 fn->private_data = NULL;
204 static void mp3dec_post_select(__a_unused struct sched *s, struct task *t)
206 struct filter_node *fn = container_of(t, struct filter_node, task);
208 struct private_mp3dec_data *pmd = fn->private_data;
209 struct btr_node *btrn = fn->btrn;
210 size_t loaded, used, len = btr_get_input_queue_size(btrn);
211 char *inbuffer, *outbuffer;
213 pmd->stream.error = 0;
215 if (btr_bytes_pending(btrn) > MP3DEC_MAX_PENDING)
217 if (need_bad_data_delay(pmd, len))
219 if (len <= pmd->input_len_barrier && btr_no_parent(btrn)) {
224 len = btr_next_buffer(btrn, &inbuffer);
227 mad_stream_buffer(&pmd->stream, (unsigned char *)inbuffer, len);
229 ret = mad_header_decode(&pmd->frame.header, &pmd->stream);
231 used = used_mad_buffer_bytes(&pmd->stream, len);
232 btr_consume(btrn, used);
233 if (pmd->stream.error == MAD_ERROR_BUFLEN) {
234 pmd->input_len_barrier = len - used;
235 ret = btr_merge(btrn);
238 } else if (pmd->stream.error != MAD_ERROR_LOSTSYNC)
239 PARA_DEBUG_LOG("header decode: %s\n",
240 mad_stream_errorstr(&pmd->stream));
243 pmd->input_len_barrier = 0;
244 pmd->samplerate = pmd->frame.header.samplerate;
245 pmd->channels = MAD_NCHANNELS(&pmd->frame.header);
246 ret = mad_frame_decode(&pmd->frame, &pmd->stream);
248 PARA_CRIT_LOG("frame decode: %d\n", ret);
249 used = used_mad_buffer_bytes(&pmd->stream, len);
250 ret = handle_decode_error(pmd, used);
251 btr_consume(btrn, used);
258 mad_synth_frame(&pmd->synth, &pmd->frame);
259 pmd->flags |= MP3DEC_FLAG_DECODE_STARTED;
261 outbuffer = para_malloc(pmd->synth.pcm.length * 4);
263 for (i = 0; i < pmd->synth.pcm.length; i++) {
264 int sample = MAD_TO_SHORT(pmd->synth.pcm.samples[0][i]);
265 write_int16_host_endian(outbuffer + loaded, sample);
267 if (MAD_NCHANNELS(&pmd->frame.header) == 2) { /* stereo */
268 sample = MAD_TO_SHORT(pmd->synth.pcm.samples[1][i]);
269 write_int16_host_endian(outbuffer + loaded, sample);
273 btr_add_output(outbuffer, loaded, btrn);
282 static void mp3dec_open(struct filter_node *fn)
284 struct private_mp3dec_data *pmd = para_calloc(sizeof(*pmd));
285 struct mp3dec_filter_args_info *mp3_conf = fn->conf;
287 fn->private_data = pmd;
288 mad_stream_init(&pmd->stream);
289 mad_frame_init(&pmd->frame);
290 mad_synth_init(&pmd->synth);
292 fn->bufsize = mp3_conf->bufsize_arg * 1024;
293 fn->buf = para_calloc(fn->bufsize);
294 if (mp3_conf->ignore_crc_given)
295 mad_stream_options(&pmd->stream, MAD_OPTION_IGNORECRC);
298 static int mp3dec_parse_config(int argc, char **argv, void **config)
301 struct mp3dec_filter_args_info *mp3_conf;
303 mp3_conf = para_calloc(sizeof(*mp3_conf));
304 ret = -E_MP3DEC_SYNTAX;
305 if (mp3dec_cmdline_parser(argc, argv, mp3_conf))
307 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
308 if (mp3_conf->bufsize_arg < 32)
310 if (mp3_conf->bufsize_arg >= INT_MAX / 1024)
319 static int mp3dec_execute(struct btr_node *btrn, const char *cmd, char **result)
321 struct filter_node *fn = btr_context(btrn);
322 struct private_mp3dec_data *pmd = fn->private_data;
324 if (!strcmp(cmd, "samplerate")) {
325 if (pmd->samplerate == 0)
326 return -ERRNO_TO_PARA_ERROR(ENAVAIL);
327 *result = make_message("%u", pmd->samplerate);
330 if (!strcmp(cmd, "channels")) {
331 if (pmd->channels == 0)
332 return -ERRNO_TO_PARA_ERROR(ENAVAIL);
333 *result = make_message("%u", pmd->channels);
336 return -ERRNO_TO_PARA_ERROR(ENOTSUP);
339 * The init function of the mp3dec filter.
341 * \param f Pointer to the filter struct to initialize.
345 void mp3dec_filter_init(struct filter *f)
347 struct mp3dec_filter_args_info dummy;
349 mp3dec_cmdline_parser_init(&dummy);
350 f->open = mp3dec_open;
352 f->close = mp3dec_close;
353 f->parse_config = mp3dec_parse_config;
354 f->pre_select = mp3dec_pre_select;
355 f->post_select = mp3dec_post_select;
356 f->execute = mp3dec_execute;
357 f->help = (struct ggo_help) {
358 .short_help = mp3dec_filter_args_info_help,
359 .detailed_help = mp3dec_filter_args_info_detailed_help