// Copyright (c) the JPEG XL Project Authors. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "lib/jxl/decode_to_jpeg.h"
#include <jxl/decode.h>
#include <algorithm>
#include <cstddef>
#include <cstdint>
#include <cstring>
#include "lib/jxl/base/span.h"
#include "lib/jxl/base/status.h"
#include "lib/jxl/common.h" // JPEGXL_ENABLE_TRANSCODE_JPEG
#include "lib/jxl/jpeg/dec_jpeg_data.h"
#include "lib/jxl/jpeg/jpeg_data.h"
namespace jxl {
#if JPEGXL_ENABLE_TRANSCODE_JPEG
JxlDecoderStatus JxlToJpegDecoder::Process(
const uint8_t** next_in,
size_t* avail_in) {
if (!inside_box_) {
JXL_WARNING(
"processing of JPEG reconstruction data outside JPEG reconstruction "
"box");
return JXL_DEC_ERROR;
}
Span<
const uint8_t> to_decode;
if (box_until_eof_) {
// Until EOF means consume all data.
to_decode = Bytes(*next_in, *avail_in);
*next_in += *avail_in;
*avail_in = 0;
}
else {
// Defined size means consume min(available, needed).
size_t avail_recon_in =
std::min<size_t>(*avail_in, box_size_ - buffer_.size());
to_decode = Bytes(*next_in, avail_recon_in);
*next_in += avail_recon_in;
*avail_in -= avail_recon_in;
}
bool old_data_exists = !buffer_.empty();
if (old_data_exists) {
// Append incoming data to buffer if we already had data in the buffer.
buffer_.insert(buffer_.end(), to_decode.data(),
to_decode.data() + to_decode.size());
to_decode = Bytes(buffer_.data(), buffer_.size());
}
if (!box_until_eof_ && to_decode.size() > box_size_) {
JXL_WARNING(
"JPEG reconstruction data to decode larger than expected");
return JXL_DEC_ERROR;
}
if (box_until_eof_ || to_decode.size() == box_size_) {
// If undefined size, or the right size, try to decode.
jpeg_data_ = make_unique<jpeg::JPEGData>();
const auto status = jpeg::DecodeJPEGData(to_decode, jpeg_data_.get());
if (status.IsFatalError())
return JXL_DEC_ERROR;
if (status) {
// Successful decoding, emit event after updating state to track that we
// are no longer parsing JPEG reconstruction data.
inside_box_ =
false;
return JXL_DEC_JPEG_RECONSTRUCTION;
}
if (box_until_eof_) {
// Unsuccessful decoding and undefined size, assume incomplete data. Copy
// the data if we haven't already.
if (!old_data_exists) {
buffer_.insert(buffer_.end(), to_decode.data(),
to_decode.data() + to_decode.size());
}
}
else {
// Unsuccessful decoding of correct amount of data, assume error.
return JXL_DEC_ERROR;
}
}
else {
// Not enough data, copy the data if we haven't already.
if (!old_data_exists) {
buffer_.insert(buffer_.end(), to_decode.data(),
to_decode.data() + to_decode.size());
}
}
return JXL_DEC_NEED_MORE_INPUT;
}
size_t JxlToJpegDecoder::NumExifMarkers(
const jpeg::JPEGData& jpeg_data) {
size_t num = 0;
for (size_t i = 0; i < jpeg_data.app_data.size(); ++i) {
if (jpeg_data.app_marker_type[i] == jxl::jpeg::AppMarkerType::kExif) {
num++;
}
}
return num;
}
size_t JxlToJpegDecoder::NumXmpMarkers(
const jpeg::JPEGData& jpeg_data) {
size_t num = 0;
for (size_t i = 0; i < jpeg_data.app_data.size(); ++i) {
if (jpeg_data.app_marker_type[i] == jxl::jpeg::AppMarkerType::kXMP) {
num++;
}
}
return num;
}
JxlDecoderStatus JxlToJpegDecoder::ExifBoxContentSize(
const jpeg::JPEGData& jpeg_data, size_t* size) {
for (size_t i = 0; i < jpeg_data.app_data.size(); ++i) {
if (jpeg_data.app_marker_type[i] == jxl::jpeg::AppMarkerType::kExif) {
if (jpeg_data.app_data[i].size() < 3 +
sizeof(jpeg::kExifTag)) {
// too small for app marker header
return JXL_DEC_ERROR;
}
// The first 4 bytes are the TIFF header from the box contents, and are
// not included in the JPEG
*size = jpeg_data.app_data[i].size() + 4 - 3 -
sizeof(jpeg::kExifTag);
return JXL_DEC_SUCCESS;
}
}
return JXL_DEC_ERROR;
}
JxlDecoderStatus JxlToJpegDecoder::XmlBoxContentSize(
const jpeg::JPEGData& jpeg_data, size_t* size) {
for (size_t i = 0; i < jpeg_data.app_data.size(); ++i) {
if (jpeg_data.app_marker_type[i] == jxl::jpeg::AppMarkerType::kXMP) {
if (jpeg_data.app_data[i].size() < 3 +
sizeof(jpeg::kXMPTag)) {
// too small for app marker header
return JXL_DEC_ERROR;
}
*size = jpeg_data.app_data[i].size() - 3 -
sizeof(jpeg::kXMPTag);
return JXL_DEC_SUCCESS;
}
}
return JXL_DEC_ERROR;
}
JxlDecoderStatus JxlToJpegDecoder::SetExif(
const uint8_t* data, size_t size,
jpeg::JPEGData* jpeg_data) {
for (size_t i = 0; i < jpeg_data->app_data.size(); ++i) {
if (jpeg_data->app_marker_type[i] == jxl::jpeg::AppMarkerType::kExif) {
if (jpeg_data->app_data[i].size() !=
size + 3 +
sizeof(jpeg::kExifTag) - 4)
return JXL_DEC_ERROR;
// The first 9 bytes are used for JPEG marker header.
jpeg_data->app_data[i][0] = 0xE1;
// The second and third byte are already filled in correctly
memcpy(jpeg_data->app_data[i].data() + 3, jpeg::kExifTag,
sizeof(jpeg::kExifTag));
// The first 4 bytes are the TIFF header from the box contents, and are
// not included in the JPEG
memcpy(jpeg_data->app_data[i].data() + 3 +
sizeof(jpeg::kExifTag),
data + 4, size - 4);
return JXL_DEC_SUCCESS;
}
}
return JXL_DEC_ERROR;
}
JxlDecoderStatus JxlToJpegDecoder::SetXmp(
const uint8_t* data, size_t size,
jpeg::JPEGData* jpeg_data) {
for (size_t i = 0; i < jpeg_data->app_data.size(); ++i) {
if (jpeg_data->app_marker_type[i] == jxl::jpeg::AppMarkerType::kXMP) {
if (jpeg_data->app_data[i].size() != size + 3 +
sizeof(jpeg::kXMPTag))
return JXL_DEC_ERROR;
// The first 9 bytes are used for JPEG marker header.
jpeg_data->app_data[i][0] = 0xE1;
// The second and third byte are already filled in correctly
memcpy(jpeg_data->app_data[i].data() + 3, jpeg::kXMPTag,
sizeof(jpeg::kXMPTag));
memcpy(jpeg_data->app_data[i].data() + 3 +
sizeof(jpeg::kXMPTag), data,
size);
return JXL_DEC_SUCCESS;
}
}
return JXL_DEC_ERROR;
}
#endif // JPEGXL_ENABLE_TRANSCODE_JPEG
}
// namespace jxl
