def ratecv(cp, size, nchannels, inrate, outrate, state, weightA=1, weightB=0):
_check_params(len(cp), size)
if nchannels < 1:
raise error("# of channels should be >= 1")
bytes_per_frame = size * nchannels
frame_count = len(cp) // bytes_per_frame
if bytes_per_frame // nchannels != size:
raise OverflowError("width * nchannels too big for a C int")
if weightA < 1 or weightB < 0:
raise error("weightA should be >= 1, weightB should be >= 0")
if len(cp) % bytes_per_frame != 0:
raise error("not a whole number of frames")
if inrate <= 0 or outrate <= 0:
raise error("sampling rate not > 0")
d = gcd(inrate, outrate)
inrate //= d
outrate //= d
d = gcd(weightA, weightB)
weightA //= d
weightB //= d
if state is None:
d = -outrate
prev_i = ffi.new('int[]', nchannels)
cur_i = ffi.new('int[]', nchannels)
else:
d, samps = state
if len(samps) != nchannels:
raise error("illegal state argument")
prev_i, cur_i = zip(*samps)
prev_i = ffi.new('int[]', prev_i)
cur_i = ffi.new('int[]', cur_i)
state_d = ffi.new('int[]', (d,))
q = frame_count // inrate
ceiling = (q + 1) * outrate
nbytes = ceiling * bytes_per_frame
rv = ffi.new("char[]", nbytes)
cpbuf = ffi.from_buffer(cp)
trim_index = lib.ratecv(rv, cpbuf, frame_count, size,
nchannels, inrate, outrate,
state_d, prev_i, cur_i,
weightA, weightB)
result = ffi.buffer(rv)[:trim_index]
d = state_d[0]
samps = zip(prev_i, cur_i)
return (result, (d, tuple(samps)))
def ratecv(cp, size, nchannels, inrate, outrate, state, weightA=1, weightB=0):
_check_params(len(cp), size)
if nchannels < 1:
raise error("# of channels should be >= 1")
bytes_per_frame = size * nchannels
frame_count = len(cp) // bytes_per_frame
if bytes_per_frame // nchannels != size:
raise OverflowError("width * nchannels too big for a C int")
if weightA < 1 or weightB < 0:
raise error("weightA should be >= 1, weightB should be >= 0")
if len(cp) % bytes_per_frame != 0:
raise error("not a whole number of frames")
if inrate <= 0 or outrate <= 0:
raise error("sampling rate not > 0")
d = gcd(inrate, outrate)
inrate //= d
outrate //= d
d = gcd(weightA, weightB)
weightA //= d
weightB //= d
if state is None:
d = -outrate
prev_i = ffi.new('int[]', nchannels)
cur_i = ffi.new('int[]', nchannels)
else:
d, samps = state
if len(samps) != nchannels:
raise error("illegal state argument")
prev_i, cur_i = zip(*samps)
prev_i = ffi.new('int[]', prev_i)
cur_i = ffi.new('int[]', cur_i)
state_d = ffi.new('int[]', (d,))
q = frame_count // inrate
ceiling = (q + 1) * outrate
nbytes = ceiling * bytes_per_frame
rv = ffi.new("unsigned char[]", nbytes)
trim_index = lib.ratecv(rv, cp, frame_count, size,
nchannels, inrate, outrate,
state_d, prev_i, cur_i,
weightA, weightB)
result = ffi.buffer(rv)[:trim_index]
d = state_d[0]
samps = zip(prev_i, cur_i)
return (result, (d, tuple(samps)))