modules/convert.c

   1 #include "modules.h"
   2 #include "graph.h"
   3 #include "assert.h"
   4
   5 struct converter {
   6     struct graphpin *in_pin, *out_pin;
   7     struct aformat src_af, dest_af;
   8 };
   9
  10 static err_t get_output_format(struct graphnode *node, struct graphpin *pin, struct aformat *af)
  11 {
  12     struct converter *c = node->extra;
  13     assert(pin == c->out_pin);
  14     *af = c->dest_af;
  15     return EOK;
  16 }
  17
  18 static err_t run(struct graphnode *node)
  19 {
  20 #define DO_CONVERT(s_T, d_T, SCALE) { \
  21     s_T *restrict s_ptr = s_buf->data; \
  22     d_T *restrict d_ptr = d_buf->data; \
  23     int i; \
  24     for (i=s_buf->n_samples * s_buf->format.channels; i; --i){ \
  25         (*(d_ptr++)) = (d_T) ((*(s_ptr++)) SCALE); \
  26     } \
  27     return EOK; }
  28
  29     struct converter *c = node->extra;
  30     struct buffer *s_buf = &c->in_pin->edge->buf,
  31                   *d_buf = &c->out_pin->edge->buf;
  32     err_t err;
  33
  34     err = buffer_alloc(d_buf, s_buf->n_samples);
  35     if (err != EOK){
  36         return err;
  37     }
  38
  39     switch (c->src_af.media){
  40         case MT_AUDIO_32F:
  41             switch (c->dest_af.media){
  42                 case MT_AUDIO_16I:
  43                     DO_CONVERT(float, short, * 32768.0)
  44                 case MT_AUDIO_32I:
  45                     DO_CONVERT(float, int, * 2147483648.0)
  46             }
  47         case MT_AUDIO_16I:
  48             switch (c->dest_af.media){
  49                 case MT_AUDIO_32F:
  50                     DO_CONVERT(short, float, / 32768.0)
  51                 case MT_AUDIO_32I:
  52                     DO_CONVERT(short, int, >> 16)
  53             }
  54         case MT_AUDIO_32I:
  55             switch (c->dest_af.media){
  56                 case MT_AUDIO_32F:
  57                     DO_CONVERT(int, float, / 2147483648.0)
  58                 case MT_AUDIO_16I:
  59                     DO_CONVERT(int, short, << 16)
  60             }
  61     }
  62     return make_error(ENOTIMPL, NULL, "conversion between these media types is not implemented");
  63 }
  64
  65 static const struct graphnode_functab functab = {
  66     NULL,   // is_acceptable_input_format
  67     NULL,   // get_ideal_input_format
  68     get_output_format,
  69     NULL,   // set_buffer
  70     run,
  71 };
  72
  73 err_t audio_converter_create(struct graphnode **node_out, struct aformat *src_af, struct aformat *dest_af)
  74 {
  75     struct graphnode *node;
  76     struct converter *restrict c;
  77     err_t err;
  78
  79     err = graphnode_create(&node, &functab, sizeof *c);
  80     if (err != EOK){
  81         return err;
  82     }
  83     c = node->extra;
  84
  85     c->src_af = *src_af;
  86     c->dest_af = *dest_af;
  87
  88     err = graphnode_add_pin(node, &c->in_pin);
  89     if (err != EOK){
  90         return err;
  91     }
  92     c->in_pin->dir = DIR_IN;
  93     c->in_pin->name = "in";
  94
  95     err = graphnode_add_pin(node, &c->out_pin);
  96     if (err != EOK){
  97         return err;
  98     }
  99     c->out_pin->dir = DIR_OUT;
 100     c->out_pin->name = "out";
 101
 102     *node_out = node;
 103     return EOK;
 104 }