a7e00a42 |
1 | /* |
2 | * Copyright (C) 2013 nu774 |
3 | * For conditions of distribution and use, see copyright notice in COPYING |
4 | */ |
5 | #if HAVE_CONFIG_H |
6 | # include "config.h" |
7 | #endif |
8 | #include <stdlib.h> |
9 | #include <string.h> |
10 | #if HAVE_STDINT_H |
11 | # include <stdint.h> |
12 | #endif |
13 | #include "pcm_reader.h" |
14 | |
15 | typedef struct pcm_float_converter_t { |
16 | pcm_reader_vtbl_t *vtbl; |
17 | pcm_reader_t *src; |
18 | pcm_sample_description_t format; |
19 | } pcm_float_converter_t; |
20 | |
21 | static inline pcm_reader_t *get_source(pcm_reader_t *reader) |
22 | { |
23 | return ((pcm_float_converter_t *)reader)->src; |
24 | } |
25 | |
26 | static const |
27 | pcm_sample_description_t *get_format(pcm_reader_t *reader) |
28 | { |
29 | return &((pcm_float_converter_t *)reader)->format; |
30 | } |
31 | |
32 | static int64_t get_length(pcm_reader_t *reader) |
33 | { |
34 | return pcm_get_length(get_source(reader)); |
35 | } |
36 | |
37 | static int64_t get_position(pcm_reader_t *reader) |
38 | { |
39 | return pcm_get_position(get_source(reader)); |
40 | } |
41 | |
42 | static int read_frames(pcm_reader_t *reader, void *buffer, unsigned nframes) |
43 | { |
44 | unsigned i; |
45 | pcm_float_converter_t *self = (pcm_float_converter_t *)reader; |
46 | const pcm_sample_description_t *sfmt = pcm_get_format(self->src); |
47 | nframes = pcm_read_frames(self->src, buffer, nframes); |
48 | if (!(sfmt->sample_type & PCM_TYPE_FLOAT)) { |
49 | int32_t *ip = buffer; |
50 | float *op = buffer; |
51 | unsigned i, count = nframes * sfmt->channels_per_frame; |
52 | for (i = 0; i < count; ++i) |
53 | op[i] = ip[i] / 2147483648.0f; |
54 | } |
55 | return nframes; |
56 | } |
57 | |
58 | static void teardown(pcm_reader_t **reader) |
59 | { |
60 | pcm_float_converter_t *self = (pcm_float_converter_t *)*reader; |
61 | pcm_teardown(&self->src); |
62 | free(self); |
63 | *reader = 0; |
64 | } |
65 | |
66 | static pcm_reader_vtbl_t my_vtable = { |
67 | get_format, get_length, get_position, read_frames, teardown |
68 | }; |
69 | |
70 | pcm_reader_t *pcm_open_float_converter(pcm_reader_t *reader) |
71 | { |
72 | pcm_float_converter_t *self = 0; |
73 | pcm_sample_description_t *fmt; |
74 | |
75 | if ((self = calloc(1, sizeof(pcm_float_converter_t))) == 0) |
76 | return 0; |
77 | self->src = reader; |
78 | self->vtbl = &my_vtable; |
79 | memcpy(&self->format, pcm_get_format(reader), sizeof(self->format)); |
80 | fmt = &self->format; |
81 | fmt->bits_per_channel = 32; |
82 | fmt->sample_type = PCM_TYPE_FLOAT; |
83 | fmt->bytes_per_frame = 4 * fmt->channels_per_frame; |
84 | return (pcm_reader_t *)self; |
85 | } |