diff options
Diffstat (limited to 'src/components')
-rw-r--r-- | src/components/rle/RleDecoder.cpp | 39 | ||||
-rw-r--r-- | src/components/rle/RleDecoder.h | 33 |
2 files changed, 72 insertions, 0 deletions
diff --git a/src/components/rle/RleDecoder.cpp b/src/components/rle/RleDecoder.cpp new file mode 100644 index 00000000..19a90fda --- /dev/null +++ b/src/components/rle/RleDecoder.cpp @@ -0,0 +1,39 @@ +#include "RleDecoder.h" + +using namespace Pinetime::Tools; + +RleDecoder::RleDecoder(const uint8_t *buffer, size_t size) : buffer{buffer}, size{size} { + +} + +RleDecoder::RleDecoder(const uint8_t *buffer, size_t size, uint16_t foregroundColor, uint16_t backgroundColor) : RleDecoder{buffer, size} { + this->foregroundColor = foregroundColor; + this->backgroundColor = backgroundColor; +} + + +void RleDecoder::DecodeNext(uint8_t *output, size_t maxBytes) { + for (;encodedBufferIndex<size; encodedBufferIndex++) { + uint8_t rl = buffer[encodedBufferIndex] - processedCount; + while (rl) { + output[bp] = color >> 8; + output[bp + 1] = color & 0xff; + bp += 2; + rl -= 1; + processedCount++; + + if (bp >= maxBytes) { + bp = 0; + y += 1; + return; + } + } + processedCount = 0; + + if (color == backgroundColor) + color = foregroundColor; + else + color = backgroundColor; + } +} + diff --git a/src/components/rle/RleDecoder.h b/src/components/rle/RleDecoder.h new file mode 100644 index 00000000..0f607fb8 --- /dev/null +++ b/src/components/rle/RleDecoder.h @@ -0,0 +1,33 @@ +#pragma once + +#include <cstdint> +#include <cstddef> + +namespace Pinetime { + namespace Tools { + /* 1-bit RLE decoder. Provide the encoded buffer to the constructor and then call DecodeNext() by + * specifying the output (decoded) buffer and the maximum number of bytes this buffer can handle. + * + * Code from https://github.com/daniel-thompson/wasp-bootloader by Daniel Thompson released under the MIT license. + */ + class RleDecoder { + public: + RleDecoder(const uint8_t* buffer, size_t size); + RleDecoder(const uint8_t* buffer, size_t size, uint16_t foregroundColor, uint16_t backgroundColor); + + void DecodeNext(uint8_t* output, size_t maxBytes); + + private: + const uint8_t* buffer; + size_t size; + + int encodedBufferIndex = 0; + int y = 0; + uint16_t bp = 0; + uint16_t foregroundColor = 0xffff; + uint16_t backgroundColor = 0; + uint16_t color = backgroundColor; + int processedCount = 0; + }; + } +} |