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 static ssize_t mp3dec(char *inbuffer, size_t len, struct filter_node *fn)
100 struct private_mp3dec_data *pmd = fn->private_data;
101 size_t copy = PARA_MIN(len, (size_t)4096);
103 if (fn->loaded + 16384 > fn->bufsize)
105 if (need_bad_data_delay(pmd, len))
107 mad_stream_buffer(&pmd->stream, (unsigned char *) inbuffer, copy);
108 pmd->stream.error = 0;
110 ret = mad_header_decode(&pmd->frame.header, &pmd->stream);
112 if (pmd->stream.error != MAD_ERROR_BUFLEN &&
113 pmd->stream.error != MAD_ERROR_LOSTSYNC)
114 PARA_DEBUG_LOG("header decode: %s\n",
115 mad_stream_errorstr(&pmd->stream));
118 fn->fc->samplerate = pmd->frame.header.samplerate;
119 fn->fc->channels = MAD_NCHANNELS(&pmd->frame.header);
120 ret = mad_frame_decode(&pmd->frame, &pmd->stream);
122 ret = handle_decode_error(pmd, len);
127 ret = copy - (pmd->stream.bufend - pmd->stream.next_frame);
128 PARA_NOTICE_LOG("skipping %d input bytes\n", ret);
131 mad_synth_frame(&pmd->synth, &pmd->frame);
132 pmd->flags |= MP3DEC_FLAG_DECODE_STARTED;
134 for (i = 0; i < pmd->synth.pcm.length; i++) {
135 int s = MAD_TO_SHORT(pmd->synth.pcm.samples[0][i]);
136 write_int16_host_endian(fn->buf + fn->loaded, s);
138 if (MAD_NCHANNELS(&pmd->frame.header) == 2) { /* stereo */
139 s = MAD_TO_SHORT(pmd->synth.pcm.samples[1][i]);
140 write_int16_host_endian(fn->buf + fn->loaded, s);
143 if (fn->loaded != fn->bufsize) /* output buffer not full */
145 PARA_ERROR_LOG("output buffer full: %zd\n", fn->loaded);
146 return -E_MP3DEC_OVERRUN;
148 if (fn->loaded + 16384 <= fn->bufsize)
151 if (pmd->stream.next_frame) { /* we still have some data */
152 size_t off = pmd->stream.bufend - pmd->stream.next_frame;
153 if (fn->loaded + 16384 <= fn->bufsize && off > 2048)
160 static size_t used_mad_buffer_bytes(struct mad_stream *s, size_t max)
166 /* we still have some data */
167 rv = s->next_frame - s->buffer;
172 static void mp3dec_close(struct filter_node *fn)
174 struct private_mp3dec_data *pmd = fn->private_data;
176 mad_synth_finish(&pmd->synth);
177 mad_frame_finish(&pmd->frame);
178 mad_stream_finish(&pmd->stream);
183 fn->private_data = NULL;
186 static void mp3dec_post_select(__a_unused struct sched *s, struct task *t)
188 struct filter_node *fn = container_of(t, struct filter_node, task);
190 struct private_mp3dec_data *pmd = fn->private_data;
191 struct btr_node *btrn = fn->btrn;
192 size_t loaded, used, len, iqs;
193 char *inbuffer, *outbuffer;
196 pmd->stream.error = 0;
198 iqs = btr_get_input_queue_size(btrn);
199 if (need_bad_data_delay(pmd, iqs))
201 ret = prepare_filter_node(fn);
206 len = btr_next_buffer(btrn, &inbuffer);
207 mad_stream_buffer(&pmd->stream, (unsigned char *)inbuffer, len);
209 ret = mad_header_decode(&pmd->frame.header, &pmd->stream);
211 used = used_mad_buffer_bytes(&pmd->stream, len);
212 btr_consume(btrn, used);
213 if (pmd->stream.error == MAD_ERROR_BUFLEN) {
214 if (len == iqs && btr_no_parent(btrn)) {
220 } else if (pmd->stream.error != MAD_ERROR_LOSTSYNC)
221 PARA_DEBUG_LOG("header decode: %s\n",
222 mad_stream_errorstr(&pmd->stream));
226 pmd->samplerate = pmd->frame.header.samplerate;
227 pmd->channels = MAD_NCHANNELS(&pmd->frame.header);
228 ret = mad_frame_decode(&pmd->frame, &pmd->stream);
230 PARA_CRIT_LOG("frame decode: %d\n", ret);
231 used = used_mad_buffer_bytes(&pmd->stream, len);
232 ret = handle_decode_error(pmd, used);
233 btr_consume(btrn, used);
240 mad_synth_frame(&pmd->synth, &pmd->frame);
241 pmd->flags |= MP3DEC_FLAG_DECODE_STARTED;
243 outbuffer = para_malloc(pmd->synth.pcm.length * 4);
245 for (i = 0; i < pmd->synth.pcm.length; i++) {
246 int sample = MAD_TO_SHORT(pmd->synth.pcm.samples[0][i]);
247 write_int16_host_endian(outbuffer + loaded, sample);
249 if (MAD_NCHANNELS(&pmd->frame.header) == 2) { /* stereo */
250 sample = MAD_TO_SHORT(pmd->synth.pcm.samples[1][i]);
251 write_int16_host_endian(outbuffer + loaded, sample);
255 btr_add_output(outbuffer, loaded, btrn);
264 static void mp3dec_open(struct filter_node *fn)
266 struct private_mp3dec_data *pmd = para_calloc(sizeof(*pmd));
267 struct mp3dec_filter_args_info *mp3_conf = fn->conf;
269 fn->private_data = pmd;
270 mad_stream_init(&pmd->stream);
271 mad_frame_init(&pmd->frame);
272 mad_synth_init(&pmd->synth);
274 fn->bufsize = mp3_conf->bufsize_arg * 1024;
275 fn->buf = para_calloc(fn->bufsize);
276 if (mp3_conf->ignore_crc_given)
277 mad_stream_options(&pmd->stream, MAD_OPTION_IGNORECRC);
280 static int mp3dec_parse_config(int argc, char **argv, void **config)
283 struct mp3dec_filter_args_info *mp3_conf;
285 mp3_conf = para_calloc(sizeof(*mp3_conf));
286 ret = -E_MP3DEC_SYNTAX;
287 if (mp3dec_cmdline_parser(argc, argv, mp3_conf))
289 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
290 if (mp3_conf->bufsize_arg < 32)
292 if (mp3_conf->bufsize_arg >= INT_MAX / 1024)
301 static int mp3dec_execute(struct btr_node *btrn, const char *cmd, char **result)
303 struct filter_node *fn = btr_context(btrn);
304 struct private_mp3dec_data *pmd = fn->private_data;
306 if (!strcmp(cmd, "samplerate")) {
307 if (pmd->samplerate == 0)
308 return -ERRNO_TO_PARA_ERROR(ENAVAIL);
309 *result = make_message("%u", pmd->samplerate);
312 if (!strcmp(cmd, "channels")) {
313 if (pmd->channels == 0)
314 return -ERRNO_TO_PARA_ERROR(ENAVAIL);
315 *result = make_message("%u", pmd->channels);
318 return -ERRNO_TO_PARA_ERROR(ENOTSUP);
321 * The init function of the mp3dec filter.
323 * \param f Pointer to the filter struct to initialize.
327 void mp3dec_filter_init(struct filter *f)
329 struct mp3dec_filter_args_info dummy;
331 mp3dec_cmdline_parser_init(&dummy);
332 f->open = mp3dec_open;
334 f->close = mp3dec_close;
335 f->parse_config = mp3dec_parse_config;
336 f->pre_select = generic_filter_pre_select;
337 f->post_select = mp3dec_post_select;
338 f->execute = mp3dec_execute;
339 f->help = (struct ggo_help) {
340 .short_help = mp3dec_filter_args_info_help,
341 .detailed_help = mp3dec_filter_args_info_detailed_help