| 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 | pcm_float_converter_t *self = (pcm_float_converter_t *)reader; |
| 45 | const pcm_sample_description_t *sfmt = pcm_get_format(self->src); |
| 46 | nframes = pcm_read_frames(self->src, buffer, nframes); |
| 47 | if (!(sfmt->sample_type & PCM_TYPE_FLOAT)) { |
| 48 | int32_t *ip = buffer; |
| 49 | float *op = buffer; |
| 50 | unsigned i, count = nframes * sfmt->channels_per_frame; |
| 51 | for (i = 0; i < count; ++i) |
| 52 | op[i] = ip[i] / 2147483648.0f; |
| 53 | } |
| 54 | return nframes; |
| 55 | } |
| 56 | |
| 57 | static void teardown(pcm_reader_t **reader) |
| 58 | { |
| 59 | pcm_float_converter_t *self = (pcm_float_converter_t *)*reader; |
| 60 | pcm_teardown(&self->src); |
| 61 | free(self); |
| 62 | *reader = 0; |
| 63 | } |
| 64 | |
| 65 | static pcm_reader_vtbl_t my_vtable = { |
| 66 | get_format, get_length, get_position, read_frames, teardown |
| 67 | }; |
| 68 | |
| 69 | pcm_reader_t *pcm_open_float_converter(pcm_reader_t *reader) |
| 70 | { |
| 71 | pcm_float_converter_t *self = 0; |
| 72 | pcm_sample_description_t *fmt; |
| 73 | |
| 74 | if ((self = calloc(1, sizeof(pcm_float_converter_t))) == 0) |
| 75 | return 0; |
| 76 | self->src = reader; |
| 77 | self->vtbl = &my_vtable; |
| 78 | memcpy(&self->format, pcm_get_format(reader), sizeof(self->format)); |
| 79 | fmt = &self->format; |
| 80 | fmt->bits_per_channel = 32; |
| 81 | fmt->sample_type = PCM_TYPE_FLOAT; |
| 82 | fmt->bytes_per_frame = 4 * fmt->channels_per_frame; |
| 83 | return (pcm_reader_t *)self; |
| 84 | } |