2 * Copyright (C) 2005-2011 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 /** Data specific to the mp3dec filter. */
28 struct private_mp3dec_data {
29 /** Information on the current mp3 stream. */
30 struct mad_stream stream;
31 /** Information about the frame which is currently decoded. */
32 struct mad_frame frame;
33 /** Contains the PCM output. */
34 struct mad_synth synth;
35 /** The number of channels of the current stream. */
36 unsigned int channels;
37 /** Current sample rate in Hz. */
38 unsigned int sample_rate;
41 /* Returns negative on serious errors. */
42 static int handle_decode_error(struct private_mp3dec_data *pmd)
44 if (!MAD_RECOVERABLE(pmd->stream.error)
45 && pmd->stream.error != MAD_ERROR_BUFLEN) {
46 PARA_ERROR_LOG("%s\n", mad_stream_errorstr(&pmd->stream));
47 return -E_MAD_FRAME_DECODE;
49 PARA_DEBUG_LOG("%s\n", mad_stream_errorstr(&pmd->stream));
53 static size_t used_mad_buffer_bytes(struct mad_stream *s, size_t max)
59 /* we still have some data */
60 rv = s->next_frame - s->buffer;
65 static void mp3dec_close(struct filter_node *fn)
67 struct private_mp3dec_data *pmd = fn->private_data;
69 mad_synth_finish(&pmd->synth);
70 mad_frame_finish(&pmd->frame);
71 mad_stream_finish(&pmd->stream);
74 fn->private_data = NULL;
77 static void mp3dec_post_select(__a_unused struct sched *s, struct task *t)
79 struct filter_node *fn = container_of(t, struct filter_node, task);
81 struct private_mp3dec_data *pmd = fn->private_data;
82 struct btr_node *btrn = fn->btrn;
83 size_t loaded, used, len, iqs;
84 char *inbuffer, *outbuffer;
87 pmd->stream.error = 0;
89 iqs = btr_get_input_queue_size(btrn);
90 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
95 btr_merge(btrn, fn->min_iqs);
96 len = btr_next_buffer(btrn, &inbuffer);
98 * Decode at most 8K in one go to give the post_select() functions of
99 * other buffer tree nodes a chance to run. This is necessary to avoid
100 * buffer underruns on slow machines.
102 len = PARA_MIN(len, (size_t)8192);
103 mad_stream_buffer(&pmd->stream, (unsigned char *)inbuffer, len);
105 ret = mad_header_decode(&pmd->frame.header, &pmd->stream);
107 used = used_mad_buffer_bytes(&pmd->stream, len);
108 btr_consume(btrn, used);
109 if (pmd->stream.error == MAD_ERROR_BUFLEN) {
110 if (len == iqs && btr_no_parent(btrn)) {
116 } else if (pmd->stream.error != MAD_ERROR_LOSTSYNC)
117 PARA_DEBUG_LOG("header decode: %s\n",
118 mad_stream_errorstr(&pmd->stream));
122 pmd->sample_rate = pmd->frame.header.samplerate;
123 pmd->channels = MAD_NCHANNELS(&pmd->frame.header);
124 ret = mad_frame_decode(&pmd->frame, &pmd->stream);
126 PARA_INFO_LOG("frame decode: %s\n", mad_stream_errorstr(&pmd->stream));
127 used = used_mad_buffer_bytes(&pmd->stream, len);
128 ret = handle_decode_error(pmd);
129 btr_consume(btrn, used);
136 mad_synth_frame(&pmd->synth, &pmd->frame);
137 outbuffer = para_malloc(pmd->synth.pcm.length * 2 * pmd->channels);
139 for (i = 0; i < pmd->synth.pcm.length; i++) {
140 int sample = MAD_TO_SHORT(pmd->synth.pcm.samples[0][i]);
141 write_int16_host_endian(outbuffer + loaded, sample);
143 if (pmd->channels == 2) { /* stereo */
144 sample = MAD_TO_SHORT(pmd->synth.pcm.samples[1][i]);
145 write_int16_host_endian(outbuffer + loaded, sample);
149 btr_add_output(outbuffer, loaded, btrn);
154 btr_remove_node(btrn);
157 static void mp3dec_open(struct filter_node *fn)
159 struct private_mp3dec_data *pmd = para_calloc(sizeof(*pmd));
160 struct mp3dec_filter_args_info *mp3_conf = fn->conf;
162 fn->private_data = pmd;
163 mad_stream_init(&pmd->stream);
164 mad_frame_init(&pmd->frame);
165 mad_synth_init(&pmd->synth);
166 if (mp3_conf->ignore_crc_given)
167 mad_stream_options(&pmd->stream, MAD_OPTION_IGNORECRC);
170 static int mp3dec_parse_config(int argc, char **argv, void **config)
173 struct mp3dec_filter_args_info *mp3_conf;
175 mp3_conf = para_calloc(sizeof(*mp3_conf));
176 ret = -E_MP3DEC_SYNTAX;
177 if (mp3dec_cmdline_parser(argc, argv, mp3_conf))
186 static int mp3dec_execute(struct btr_node *btrn, const char *cmd, char **result)
188 struct filter_node *fn = btr_context(btrn);
189 struct private_mp3dec_data *pmd = fn->private_data;
191 return decoder_execute(cmd, pmd->sample_rate, pmd->channels, result);
194 static void mp3dec_free_config(void *conf)
196 mp3dec_cmdline_parser_free(conf);
199 * The init function of the mp3dec filter.
201 * \param f Pointer to the filter struct to initialize.
205 void mp3dec_filter_init(struct filter *f)
207 struct mp3dec_filter_args_info dummy;
209 mp3dec_cmdline_parser_init(&dummy);
210 f->open = mp3dec_open;
211 f->close = mp3dec_close;
212 f->parse_config = mp3dec_parse_config;
213 f->free_config = mp3dec_free_config;
214 f->pre_select = generic_filter_pre_select;
215 f->post_select = mp3dec_post_select;
216 f->execute = mp3dec_execute;
217 f->help = (struct ggo_help) {
218 .short_help = mp3dec_filter_args_info_help,
219 .detailed_help = mp3dec_filter_args_info_detailed_help