| 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_sint16_converter_t { |
| 16 | pcm_reader_vtbl_t *vtbl; |
| 17 | pcm_reader_t *src; |
| 18 | pcm_sample_description_t format; |
| 19 | void *pivot; |
| 20 | unsigned capacity; |
| 21 | } pcm_sint16_converter_t; |
| 22 | |
| 23 | static inline pcm_reader_t *get_source(pcm_reader_t *reader) |
| 24 | { |
| 25 | return ((pcm_sint16_converter_t *)reader)->src; |
| 26 | } |
| 27 | |
| 28 | static const |
| 29 | pcm_sample_description_t *get_format(pcm_reader_t *reader) |
| 30 | { |
| 31 | return &((pcm_sint16_converter_t *)reader)->format; |
| 32 | } |
| 33 | |
| 34 | static int64_t get_length(pcm_reader_t *reader) |
| 35 | { |
| 36 | return pcm_get_length(get_source(reader)); |
| 37 | } |
| 38 | |
| 39 | static int64_t get_position(pcm_reader_t *reader) |
| 40 | { |
| 41 | return pcm_get_position(get_source(reader)); |
| 42 | } |
| 43 | |
| 44 | static int read_frames(pcm_reader_t *reader, void *buffer, unsigned nframes) |
| 45 | { |
| 46 | unsigned i, count; |
| 47 | pcm_sint16_converter_t *self = (pcm_sint16_converter_t *)reader; |
| 48 | const pcm_sample_description_t *sfmt = pcm_get_format(self->src); |
| 49 | unsigned bytes = nframes * sfmt->bytes_per_frame; |
| 50 | if (self->capacity < bytes) { |
| 51 | void *p = realloc(self->pivot, bytes); |
| 52 | if (!p) return -1; |
| 53 | self->pivot = p; |
| 54 | self->capacity = bytes; |
| 55 | } |
| 56 | nframes = pcm_read_frames(self->src, self->pivot, nframes); |
| 57 | count = nframes * sfmt->channels_per_frame; |
| 58 | if (PCM_IS_FLOAT(sfmt)) { |
| 59 | float *ip = self->pivot; |
| 60 | int16_t *op = buffer; |
| 61 | for (i = 0; i < count; ++i) |
| 62 | op[i] = pcm_clip(ip[i] * 32768.0, -32768.0, 32767.0); |
| 63 | } else { |
| 64 | int32_t *ip = self->pivot; |
| 65 | int16_t *op = buffer; |
| 66 | if (sfmt->bits_per_channel <= 16) { |
| 67 | for (i = 0; i < count; ++i) |
| 68 | op[i] = ip[i] >> 16; |
| 69 | } else { |
| 70 | for (i = 0; i < count; ++i) { |
| 71 | int n = ((ip[i] >> 15) + 1) >> 1; |
| 72 | op[i] = (n == 0x8000) ? 0x7fff : n; |
| 73 | } |
| 74 | } |
| 75 | } |
| 76 | return nframes; |
| 77 | } |
| 78 | |
| 79 | static void teardown(pcm_reader_t **reader) |
| 80 | { |
| 81 | pcm_sint16_converter_t *self = (pcm_sint16_converter_t *)*reader; |
| 82 | pcm_teardown(&self->src); |
| 83 | free(self->pivot); |
| 84 | free(self); |
| 85 | *reader = 0; |
| 86 | } |
| 87 | |
| 88 | static pcm_reader_vtbl_t my_vtable = { |
| 89 | get_format, get_length, get_position, read_frames, teardown |
| 90 | }; |
| 91 | |
| 92 | pcm_reader_t *pcm_open_sint16_converter(pcm_reader_t *reader) |
| 93 | { |
| 94 | pcm_sint16_converter_t *self = 0; |
| 95 | pcm_sample_description_t *fmt; |
| 96 | |
| 97 | if ((self = calloc(1, sizeof(pcm_sint16_converter_t))) == 0) |
| 98 | return 0; |
| 99 | self->src = reader; |
| 100 | self->vtbl = &my_vtable; |
| 101 | memcpy(&self->format, pcm_get_format(reader), sizeof(self->format)); |
| 102 | fmt = &self->format; |
| 103 | fmt->bits_per_channel = 16; |
| 104 | fmt->sample_type = PCM_TYPE_SINT; |
| 105 | fmt->bytes_per_frame = 2 * fmt->channels_per_frame; |
| 106 | return (pcm_reader_t *)self; |
| 107 | } |