circuitpython/shared-module/gifio/GifWriter.h
Jeff Epler 7d6ac96001 GifWriter: improve efficiency
* Increase colorspace conversion efficiency.
   This not only avoids a function call, it avoids the time-consuming
   switch statement in conver_pixel (replacing it with a single
   conditional on the byteswap flag + accounting for BGR/RGB during
   palette creation)

 * Buffer all the bytes of a single frame together.  By reducing
   low level write calls we get a decent speed increase even though
   it increases data-shuffling a bit.

Together with some other changes that enable "double buffered" camera
capture, this gets me to 8.8fps capturing QVGA (320x240) gifs and
11fps capturing 240x240 square gifs.
2021-10-26 11:11:28 -05:00

45 lines
1.6 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* 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.
*/
#pragma once
#include "py/obj.h"
#include "py/stream.h"
#include "shared-bindings/displayio/__init__.h"
typedef struct gifio_gifwriter {
mp_obj_base_t base;
mp_obj_t *file;
const mp_stream_p_t *file_proto;
displayio_colorspace_t colorspace;
int width, height;
int error;
uint8_t *data;
size_t cur, size;
bool own_file;
bool byteswap;
} gifio_gifwriter_t;