media/libspeex_resampler/03_set-skip-frac.patch

   1 # HG changeset patch
   2 # User Karl Tomlinson <karlt+@karlt.net>
   3 b=913854 add speex_resampler_set_skip_frac_num r=jmspeex
   4
   5 This allows a client to align output samples consistently for independent
   6 resampling of contiguous input buffers.
   7
   8 diff --git a/src/resample.c b/src/resample.c
   9 --- a/src/resample.c
  10 +++ b/src/resample.c
  11 @@ -1128,16 +1128,28 @@ EXPORT int speex_resampler_get_output_la
  12  EXPORT int speex_resampler_skip_zeros(SpeexResamplerState *st)
  13  {
  14     spx_uint32_t i;
  15     for (i=0;i<st->nb_channels;i++)
  16        st->last_sample[i] = st->filt_len/2;
  17     return RESAMPLER_ERR_SUCCESS;
  18  }
  19
  20 +EXPORT int speex_resampler_set_skip_frac_num(SpeexResamplerState *st, spx_uint32_t skip_frac_num)
  21 +{
  22 +   spx_uint32_t i;
  23 +   spx_uint32_t last_sample = skip_frac_num / st->den_rate;
  24 +   spx_uint32_t samp_frac_num = skip_frac_num % st->den_rate;
  25 +   for (i=0;i<st->nb_channels;i++) {
  26 +      st->last_sample[i] = last_sample;
  27 +      st->samp_frac_num[i] = samp_frac_num;
  28 +   }
  29 +   return RESAMPLER_ERR_SUCCESS;
  30 +}
  31 +
  32  EXPORT int speex_resampler_reset_mem(SpeexResamplerState *st)
  33  {
  34     spx_uint32_t i;
  35     for (i=0;i<st->nb_channels;i++)
  36     {
  37        st->last_sample[i] = 0;
  38        st->magic_samples[i] = 0;
  39        st->samp_frac_num[i] = 0;
  40 diff --git a/src/speex_resampler.h b/src/speex_resampler.h
  41 --- a/src/speex_resampler.h
  42 +++ b/src/speex_resampler.h
  43 @@ -69,16 +69,17 @@
  44  #define speex_resampler_get_quality CAT_PREFIX(RANDOM_PREFIX,_resampler_get_quality)
  45  #define speex_resampler_set_input_stride CAT_PREFIX(RANDOM_PREFIX,_resampler_set_input_stride)
  46  #define speex_resampler_get_input_stride CAT_PREFIX(RANDOM_PREFIX,_resampler_get_input_stride)
  47  #define speex_resampler_set_output_stride CAT_PREFIX(RANDOM_PREFIX,_resampler_set_output_stride)
  48  #define speex_resampler_get_output_stride CAT_PREFIX(RANDOM_PREFIX,_resampler_get_output_stride)
  49  #define speex_resampler_get_input_latency CAT_PREFIX(RANDOM_PREFIX,_resampler_get_input_latency)
  50  #define speex_resampler_get_output_latency CAT_PREFIX(RANDOM_PREFIX,_resampler_get_output_latency)
  51  #define speex_resampler_skip_zeros CAT_PREFIX(RANDOM_PREFIX,_resampler_skip_zeros)
  52 +#define speex_resampler_set_skip_frac_num CAT_PREFIX(RANDOM_PREFIX,_resampler_set_skip_frac_num)
  53  #define speex_resampler_reset_mem CAT_PREFIX(RANDOM_PREFIX,_resampler_reset_mem)
  54  #define speex_resampler_strerror CAT_PREFIX(RANDOM_PREFIX,_resampler_strerror)
  55
  56  #define spx_int16_t short
  57  #define spx_int32_t int
  58  #define spx_uint16_t unsigned short
  59  #define spx_uint32_t unsigned int
  60
  61 @@ -317,16 +318,32 @@ int speex_resampler_get_output_latency(S
  62   * resampler. It is recommended to use that when resampling an audio file, as
  63   * it will generate a file with the same length. For real-time processing,
  64   * it is probably easier not to use this call (so that the output duration
  65   * is the same for the first frame).
  66   * @param st Resampler state
  67   */
  68  int speex_resampler_skip_zeros(SpeexResamplerState *st);
  69
  70 +/** Set the numerator in a fraction determining the advance through input
  71 + * samples before writing any output samples. The denominator of the fraction
  72 + * is the value returned from speex_resampler_get_ratio() in ratio_den. This
  73 + * is only useful before starting to use a newly created or reset resampler.
  74 + * If the first input sample is interpreted as the signal at time
  75 + * input_latency*in_rate, then the first output sample represents the signal
  76 + * at the time frac_num/ratio_num*out_rate.
  77 + * This is intended for careful alignment of output sample points wrt input
  78 + * sample points. Large values are not an efficient offset into the in buffer.
  79 + * @param st Resampler state
  80 + * @param skip_frac_num Numerator of the offset fraction,
  81 + *                      between 0 and ratio_den-1.
  82 + */
  83 +int speex_resampler_set_skip_frac_num(SpeexResamplerState *st,
  84 +                                      spx_uint32_t skip_frac_num);
  85 +
  86  /** Reset a resampler so a new (unrelated) stream can be processed.
  87   * @param st Resampler state
  88   */
  89  int speex_resampler_reset_mem(SpeexResamplerState *st);
  90
  91  /** Returns the English meaning for an error code
  92   * @param err Error code
  93   * @return English string