101 lines
4.4 KiB
C
101 lines
4.4 KiB
C
/*
|
|
* This file is part of the CircuitPython project, https://github.com/adafruit/circuitpython
|
|
*
|
|
* The MIT License (MIT)
|
|
*
|
|
* Copyright (c) 2021 Jeff Epler for Adafruit Industries
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
* THE SOFTWARE.
|
|
*/
|
|
|
|
#include "py/obj.h"
|
|
#include "py/runtime.h"
|
|
|
|
#include "shared-bindings/bitops/__init__.h"
|
|
|
|
//| """Routines for low-level manipulation of binary data"""
|
|
|
|
//| def bit_transpose(
|
|
//| input: ReadableBuffer, output: WriteableBuffer, width: int = 8
|
|
//| ) -> WriteableBuffer:
|
|
//| """ "Transpose" a buffer by assembling each output byte with bits taken from each of ``width`` different input bytes.
|
|
//|
|
|
//| This can be useful to convert a sequence of pixel values into a single
|
|
//| stream of bytes suitable for sending via a parallel conversion method.
|
|
//|
|
|
//| The number of bytes in the input buffer must be a multiple of the width,
|
|
//| and the width can be any value from 2 to 8. If the width is fewer than 8,
|
|
//| then the remaining (less significant) bits of the output are set to zero.
|
|
//|
|
|
//| Let ``stride = len(input)//width``. Then the first byte is made out of the
|
|
//| most significant bits of ``[input[0], input[stride], input[2*stride], ...]``.
|
|
//| The second byte is made out of the second bits, and so on until the 8th output
|
|
//| byte which is made of the first bits of ``input[1], input[1+stride,
|
|
//| input[2*stride], ...]``.
|
|
//|
|
|
//| The required output buffer size is ``len(input) * 8 // width``.
|
|
//|
|
|
//| Returns the output buffer."""
|
|
//| ...
|
|
|
|
STATIC mp_obj_t bit_transpose(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
|
|
enum { ARG_input, ARG_output, ARG_width };
|
|
static const mp_arg_t allowed_args[] = {
|
|
{ MP_QSTR_input, MP_ARG_OBJ | MP_ARG_REQUIRED },
|
|
{ MP_QSTR_output, MP_ARG_OBJ | MP_ARG_REQUIRED },
|
|
{ MP_QSTR_width, MP_ARG_INT, { .u_int = 8 } },
|
|
};
|
|
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
|
|
mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
|
|
|
|
mp_int_t width = mp_arg_validate_int_range(args[ARG_width].u_int, 2, 8, MP_QSTR_width);
|
|
|
|
mp_buffer_info_t input_bufinfo;
|
|
mp_get_buffer_raise(args[ARG_input].u_obj, &input_bufinfo, MP_BUFFER_READ);
|
|
int inlen = input_bufinfo.len;
|
|
if (inlen % width != 0) {
|
|
mp_raise_ValueError_varg(translate("Input buffer length (%d) must be a multiple of the strand count (%d)"), inlen, width);
|
|
}
|
|
|
|
mp_buffer_info_t output_bufinfo;
|
|
mp_get_buffer_raise(args[ARG_output].u_obj, &output_bufinfo, MP_BUFFER_WRITE);
|
|
int avail = output_bufinfo.len;
|
|
int outlen = 8 * (inlen / width);
|
|
|
|
mp_arg_validate_length_min(avail, outlen, MP_QSTR_output);
|
|
|
|
common_hal_bitops_bit_transpose(output_bufinfo.buf, input_bufinfo.buf, inlen, width);
|
|
return args[ARG_output].u_obj;
|
|
}
|
|
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(bitops_bit_transpose_obj, 0, bit_transpose);
|
|
|
|
STATIC const mp_rom_map_elem_t bitops_module_globals_table[] = {
|
|
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_bitops) },
|
|
{ MP_ROM_QSTR(MP_QSTR_bit_transpose), MP_ROM_PTR(&bitops_bit_transpose_obj) },
|
|
};
|
|
|
|
STATIC MP_DEFINE_CONST_DICT(bitops_module_globals, bitops_module_globals_table);
|
|
|
|
const mp_obj_module_t bitops_module = {
|
|
.base = { &mp_type_module },
|
|
.globals = (mp_obj_dict_t *)&bitops_module_globals,
|
|
};
|
|
|
|
MP_REGISTER_MODULE(MP_QSTR_bitops, bitops_module, CIRCUITPY_BITOPS);
|