2 * Copyright (C) 2005-2013 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. */
13 #include "mp3dec_filter.cmdline.h"
17 #include "buffer_tree.h"
22 /** Convert a sample value from libmad to a signed short. */
23 #define MAD_TO_SHORT(f) (f) >= MAD_F_ONE? SHRT_MAX :\
24 (f) <= -MAD_F_ONE? -SHRT_MAX : (signed short) ((f) >> (MAD_F_FRACBITS - 15))
26 /** Data specific to the mp3dec filter. */
27 struct private_mp3dec_data
{
28 /** Information on the current mp3 stream. */
29 struct mad_stream stream
;
30 /** Information about the frame which is currently decoded. */
31 struct mad_frame frame
;
32 /** Contains the PCM output. */
33 struct mad_synth synth
;
34 /** The number of channels of the current stream. */
35 unsigned int channels
;
36 /** Current sample rate in Hz. */
37 unsigned int sample_rate
;
40 /* Returns negative on serious errors. */
41 static int handle_decode_error(struct private_mp3dec_data
*pmd
)
43 if (!MAD_RECOVERABLE(pmd
->stream
.error
)
44 && pmd
->stream
.error
!= MAD_ERROR_BUFLEN
) {
45 PARA_ERROR_LOG("%s\n", mad_stream_errorstr(&pmd
->stream
));
46 return -E_MAD_FRAME_DECODE
;
48 PARA_DEBUG_LOG("%s\n", mad_stream_errorstr(&pmd
->stream
));
52 static void mp3dec_consume(struct btr_node
*btrn
, struct mad_stream
*s
,
59 else { /* we still have some data */
60 used
= s
->next_frame
- s
->buffer
;
63 btr_consume(btrn
, used
);
66 static void mp3dec_close(struct filter_node
*fn
)
68 struct private_mp3dec_data
*pmd
= fn
->private_data
;
70 mad_synth_finish(&pmd
->synth
);
71 mad_frame_finish(&pmd
->frame
);
72 mad_stream_finish(&pmd
->stream
);
75 fn
->private_data
= NULL
;
78 #define MP3DEC_MAX_FRAME 8192
80 static int mp3dec_post_select(__a_unused
struct sched
*s
, struct task
*t
)
82 struct filter_node
*fn
= container_of(t
, struct filter_node
, task
);
84 struct private_mp3dec_data
*pmd
= fn
->private_data
;
85 struct btr_node
*btrn
= fn
->btrn
;
86 size_t loaded
= 0, len
, iqs
;
87 char *inbuffer
, *outbuffer
;
90 pmd
->stream
.error
= 0;
91 iqs
= btr_get_input_queue_size(btrn
);
92 ret
= btr_node_status(btrn
, fn
->min_iqs
, BTR_NT_INTERNAL
);
97 btr_merge(btrn
, fn
->min_iqs
);
98 len
= btr_next_buffer(btrn
, &inbuffer
);
100 * Decode at most 8K in one go to give the post_select() functions of
101 * other buffer tree nodes a chance to run. This is necessary to avoid
102 * buffer underruns on slow machines.
104 len
= PARA_MIN(len
, (size_t)MP3DEC_MAX_FRAME
);
105 mad_stream_buffer(&pmd
->stream
, (unsigned char *)inbuffer
, len
);
107 ret
= mad_header_decode(&pmd
->frame
.header
, &pmd
->stream
);
109 mp3dec_consume(btrn
, &pmd
->stream
, len
);
110 if (pmd
->stream
.error
== MAD_ERROR_BUFLEN
) {
111 if (len
== iqs
&& btr_no_parent(btrn
)) {
116 ret
= -E_MP3DEC_CORRUPT
;
117 if (fn
->min_iqs
> MP3DEC_MAX_FRAME
)
124 pmd
->sample_rate
= pmd
->frame
.header
.samplerate
;
125 pmd
->channels
= MAD_NCHANNELS(&pmd
->frame
.header
);
127 ret
= mad_frame_decode(&pmd
->frame
, &pmd
->stream
);
129 ret
= handle_decode_error(pmd
);
132 mad_stream_sync(&pmd
->stream
);
133 if (pmd
->stream
.error
== MAD_ERROR_BUFLEN
) {
135 if (len
== iqs
&& btr_no_parent(btrn
))
138 ret
= -E_MP3DEC_CORRUPT
;
139 if (fn
->min_iqs
> MP3DEC_MAX_FRAME
)
141 mp3dec_consume(btrn
, &pmd
->stream
, len
);
144 if (pmd
->stream
.error
!= MAD_ERROR_BADDATAPTR
)
146 mp3dec_consume(btrn
, &pmd
->stream
, len
);
150 mad_synth_frame(&pmd
->synth
, &pmd
->frame
);
151 outbuffer
= para_malloc(pmd
->synth
.pcm
.length
* 2 * pmd
->channels
);
153 for (i
= 0; i
< pmd
->synth
.pcm
.length
; i
++) {
154 int sample
= MAD_TO_SHORT(pmd
->synth
.pcm
.samples
[0][i
]);
155 write_int16_host_endian(outbuffer
+ loaded
, sample
);
157 if (pmd
->channels
== 2) { /* stereo */
158 sample
= MAD_TO_SHORT(pmd
->synth
.pcm
.samples
[1][i
]);
159 write_int16_host_endian(outbuffer
+ loaded
, sample
);
163 btr_add_output(outbuffer
, loaded
, btrn
);
167 btr_remove_node(&fn
->btrn
);
171 static void mp3dec_open(struct filter_node
*fn
)
173 struct private_mp3dec_data
*pmd
= para_calloc(sizeof(*pmd
));
174 struct mp3dec_filter_args_info
*mp3_conf
= fn
->conf
;
176 fn
->private_data
= pmd
;
177 mad_stream_init(&pmd
->stream
);
178 mad_frame_init(&pmd
->frame
);
179 mad_synth_init(&pmd
->synth
);
180 if (mp3_conf
->ignore_crc_given
)
181 mad_stream_options(&pmd
->stream
, MAD_OPTION_IGNORECRC
);
184 static int mp3dec_parse_config(int argc
, char **argv
, void **config
)
186 struct mp3dec_filter_args_info
*conf
= para_calloc(sizeof(*conf
));
188 mp3dec_filter_cmdline_parser(argc
, argv
, conf
);
193 static int mp3dec_execute(struct btr_node
*btrn
, const char *cmd
, char **result
)
195 struct filter_node
*fn
= btr_context(btrn
);
196 struct private_mp3dec_data
*pmd
= fn
->private_data
;
198 return decoder_execute(cmd
, pmd
->sample_rate
, pmd
->channels
, result
);
201 static void mp3dec_free_config(void *conf
)
203 mp3dec_filter_cmdline_parser_free(conf
);
206 * The init function of the mp3dec filter.
208 * \param f Pointer to the filter struct to initialize.
212 void mp3dec_filter_init(struct filter
*f
)
214 struct mp3dec_filter_args_info dummy
;
216 mp3dec_filter_cmdline_parser_init(&dummy
);
217 f
->open
= mp3dec_open
;
218 f
->close
= mp3dec_close
;
219 f
->parse_config
= mp3dec_parse_config
;
220 f
->free_config
= mp3dec_free_config
;
221 f
->pre_select
= generic_filter_pre_select
;
222 f
->post_select
= mp3dec_post_select
;
223 f
->execute
= mp3dec_execute
;
224 f
->help
= (struct ggo_help
)DEFINE_GGO_HELP(mp3dec_filter
);