From 998f4de65ebccf638b19a90172db74b2dc469c78 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Wed, 24 Jun 2020 14:15:15 +0100 Subject: android: Introduce JPEG encoding Provide an encoder interface and implement a JPEG encoder using libjpeg. Reviewed-by: Jacopo Mondi Signed-off-by: Kieran Bingham --- src/android/jpeg/encoder_libjpeg.cpp | 218 +++++++++++++++++++++++++++++++++++ 1 file changed, 218 insertions(+) create mode 100644 src/android/jpeg/encoder_libjpeg.cpp (limited to 'src/android/jpeg/encoder_libjpeg.cpp') diff --git a/src/android/jpeg/encoder_libjpeg.cpp b/src/android/jpeg/encoder_libjpeg.cpp new file mode 100644 index 00000000..977538ce --- /dev/null +++ b/src/android/jpeg/encoder_libjpeg.cpp @@ -0,0 +1,218 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2020, Google Inc. + * + * encoder_libjpeg.cpp - JPEG encoding using libjpeg native API + */ + +#include "encoder_libjpeg.h" + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include "libcamera/internal/formats.h" +#include "libcamera/internal/log.h" + +using namespace libcamera; + +LOG_DEFINE_CATEGORY(JPEG) + +namespace { + +struct JPEGPixelFormatInfo { + J_COLOR_SPACE colorSpace; + const PixelFormatInfo &pixelFormatInfo; + bool nvSwap; +}; + +const std::map pixelInfo{ + { formats::R8, { JCS_GRAYSCALE, PixelFormatInfo::info(formats::R8), false } }, + + { formats::RGB888, { JCS_EXT_BGR, PixelFormatInfo::info(formats::RGB888), false } }, + { formats::BGR888, { JCS_EXT_RGB, PixelFormatInfo::info(formats::BGR888), false } }, + + { formats::NV12, { JCS_YCbCr, PixelFormatInfo::info(formats::NV12), false } }, + { formats::NV21, { JCS_YCbCr, PixelFormatInfo::info(formats::NV21), true } }, + { formats::NV16, { JCS_YCbCr, PixelFormatInfo::info(formats::NV16), false } }, + { formats::NV61, { JCS_YCbCr, PixelFormatInfo::info(formats::NV61), true } }, + { formats::NV24, { JCS_YCbCr, PixelFormatInfo::info(formats::NV24), false } }, + { formats::NV42, { JCS_YCbCr, PixelFormatInfo::info(formats::NV42), true } }, +}; + +const struct JPEGPixelFormatInfo &findPixelInfo(const PixelFormat &format) +{ + static const struct JPEGPixelFormatInfo invalidPixelFormat { + JCS_UNKNOWN, PixelFormatInfo(), false + }; + + const auto iter = pixelInfo.find(format); + if (iter == pixelInfo.end()) { + LOG(JPEG, Error) << "Unsupported pixel format for JPEG encoder: " + << format.toString(); + return invalidPixelFormat; + } + + return iter->second; +} + +} /* namespace */ + +EncoderLibJpeg::EncoderLibJpeg() + : quality_(95) +{ + /* \todo Expand error handling coverage with a custom handler. */ + compress_.err = jpeg_std_error(&jerr_); + + jpeg_create_compress(&compress_); +} + +EncoderLibJpeg::~EncoderLibJpeg() +{ + jpeg_destroy_compress(&compress_); +} + +int EncoderLibJpeg::configure(const StreamConfiguration &cfg) +{ + const struct JPEGPixelFormatInfo info = findPixelInfo(cfg.pixelFormat); + if (info.colorSpace == JCS_UNKNOWN) + return -ENOTSUP; + + compress_.image_width = cfg.size.width; + compress_.image_height = cfg.size.height; + compress_.in_color_space = info.colorSpace; + + compress_.input_components = info.colorSpace == JCS_GRAYSCALE ? 1 : 3; + + jpeg_set_defaults(&compress_); + jpeg_set_quality(&compress_, quality_, TRUE); + + pixelFormatInfo_ = &info.pixelFormatInfo; + + nv_ = pixelFormatInfo_->numPlanes() == 2; + nvSwap_ = info.nvSwap; + + return 0; +} + +void EncoderLibJpeg::compressRGB(const libcamera::MappedBuffer *frame) +{ + unsigned char *src = static_cast(frame->maps()[0].data()); + /* \todo Stride information should come from buffer configuration. */ + unsigned int stride = pixelFormatInfo_->stride(compress_.image_width, 0); + + JSAMPROW row_pointer[1]; + + while (compress_.next_scanline < compress_.image_height) { + row_pointer[0] = &src[compress_.next_scanline * stride]; + jpeg_write_scanlines(&compress_, row_pointer, 1); + } +} + +/* + * Compress the incoming buffer from a supported NV format. + * This naively unpacks the semi-planar NV12 to a YUV888 format for libjpeg. + */ +void EncoderLibJpeg::compressNV(const libcamera::MappedBuffer *frame) +{ + uint8_t tmprowbuf[compress_.image_width * 3]; + + /* + * \todo Use the raw api, and only unpack the cb/cr samples to new line + * buffers. If possible, see if we can set appropriate pixel strides + * too to save even that copy. + * + * Possible hints at: + * https://sourceforge.net/p/libjpeg/mailman/message/30815123/ + */ + unsigned int y_stride = pixelFormatInfo_->stride(compress_.image_width, 0); + unsigned int c_stride = pixelFormatInfo_->stride(compress_.image_width, 1); + + unsigned int horzSubSample = 2 * compress_.image_width / c_stride; + unsigned int vertSubSample = pixelFormatInfo_->planes[1].verticalSubSampling; + + unsigned int c_inc = horzSubSample == 1 ? 2 : 0; + unsigned int cb_pos = nvSwap_ ? 1 : 0; + unsigned int cr_pos = nvSwap_ ? 0 : 1; + + const unsigned char *src = static_cast(frame->maps()[0].data()); + const unsigned char *src_c = src + y_stride * compress_.image_height; + + JSAMPROW row_pointer[1]; + row_pointer[0] = &tmprowbuf[0]; + + for (unsigned int y = 0; y < compress_.image_height; y++) { + unsigned char *dst = &tmprowbuf[0]; + + const unsigned char *src_y = src + y * compress_.image_width; + const unsigned char *src_cb = src_c + (y / vertSubSample) * c_stride + cb_pos; + const unsigned char *src_cr = src_c + (y / vertSubSample) * c_stride + cr_pos; + + for (unsigned int x = 0; x < compress_.image_width; x += 2) { + dst[0] = *src_y; + dst[1] = *src_cb; + dst[2] = *src_cr; + src_y++; + src_cb += c_inc; + src_cr += c_inc; + dst += 3; + + dst[0] = *src_y; + dst[1] = *src_cb; + dst[2] = *src_cr; + src_y++; + src_cb += 2; + src_cr += 2; + dst += 3; + } + + jpeg_write_scanlines(&compress_, row_pointer, 1); + } +} + +int EncoderLibJpeg::encode(const FrameBuffer *source, + const libcamera::Span &dest) +{ + MappedFrameBuffer frame(source, PROT_READ); + if (!frame.isValid()) { + LOG(JPEG, Error) << "Failed to map FrameBuffer : " + << strerror(frame.error()); + return frame.error(); + } + + unsigned char *destination = dest.data(); + unsigned long size = dest.size(); + + /* + * The jpeg_mem_dest will reallocate if the required size is not + * sufficient. That means the output won't be written to the correct + * buffers. + * + * \todo Implement our own custom memory destination to prevent + * reallocation and prefer failure with correct reporting. + */ + jpeg_mem_dest(&compress_, &destination, &size); + + jpeg_start_compress(&compress_, TRUE); + + LOG(JPEG, Debug) << "JPEG Encode Starting:" << compress_.image_width + << "x" << compress_.image_height; + + if (nv_) + compressNV(&frame); + else + compressRGB(&frame); + + jpeg_finish_compress(&compress_); + + return size; +} -- cgit v1.2.1