Camera orientation handling is added for jpeg files

modules/imgcodecs/CMakeLists.txt

@@ -61,6 +61,8 @@ list(APPEND grfmt_hdrs ${CMAKE_CURRENT_LIST_DIR}/src/bitstrm.hpp)
 list(APPEND grfmt_srcs ${CMAKE_CURRENT_LIST_DIR}/src/bitstrm.cpp)
 list(APPEND grfmt_hdrs ${CMAKE_CURRENT_LIST_DIR}/src/rgbe.hpp)
 list(APPEND grfmt_srcs ${CMAKE_CURRENT_LIST_DIR}/src/rgbe.cpp)
+list(APPEND grfmt_hdrs ${CMAKE_CURRENT_LIST_DIR}/src/jpeg_exif.hpp)
+list(APPEND grfmt_srcs ${CMAKE_CURRENT_LIST_DIR}/src/jpeg_exif.cpp)
 
 source_group("Src\\grfmts" FILES ${grfmt_hdrs} ${grfmt_srcs})
 

modules/imgcodecs/src/grfmt_jpeg.cpp

@@ -41,6 +41,7 @@
 
 #include "precomp.hpp"
 #include "grfmt_jpeg.hpp"
+#include "jpeg_exif.hpp"
 
 #ifdef HAVE_JPEG
 
@@ -177,6 +178,7 @@ JpegDecoder::JpegDecoder()
     m_state = 0;
     m_f = 0;
     m_buf_supported = true;
+    m_orientation = JPEG_ORIENTATION_TL;
 }
 
 
@@ -253,12 +255,64 @@ bool  JpegDecoder::readHeader()
         }
     }
 
+    m_orientation = getOrientation();
+
     if( !result )
         close();
 
     return result;
 }
 
+int JpegDecoder::getOrientation()
+{
+    int orientation = JPEG_ORIENTATION_TL;
+
+    ExifReader reader( m_filename );
+    if( reader.parse() )
+    {
+        orientation = reader.getTag( ORIENTATION ).field_u16;//orientation is unsigned short, so check field_u16
+    }
+
+    return orientation;
+}
+
+void JpegDecoder::setOrientation(Mat& img)
+{
+    switch( m_orientation )
+    {
+        case    JPEG_ORIENTATION_TL: //0th row == visual top, 0th column == visual left-hand side
+            //do nothing, the image already has proper orientation
+            break;
+        case    JPEG_ORIENTATION_TR: //0th row == visual top, 0th column == visual right-hand side
+            flip(img, img, 1); //flip horizontally
+            break;
+        case    JPEG_ORIENTATION_BR: //0th row == visual bottom, 0th column == visual right-hand side
+            flip(img, img, -1);//flip both horizontally and vertically
+            break;
+        case    JPEG_ORIENTATION_BL: //0th row == visual bottom, 0th column == visual left-hand side
+            flip(img, img, 0); //flip vertically
+            break;
+        case    JPEG_ORIENTATION_LT: //0th row == visual left-hand side, 0th column == visual top
+            transpose(img, img);
+            break;
+        case    JPEG_ORIENTATION_RT: //0th row == visual right-hand side, 0th column == visual top
+            transpose(img, img);
+            flip(img, img, 1); //flip horizontally
+            break;
+        case    JPEG_ORIENTATION_RB: //0th row == visual right-hand side, 0th column == visual bottom
+            transpose(img, img);
+            flip(img, img, -1); //flip both horizontally and vertically
+            break;
+        case    JPEG_ORIENTATION_LB: //0th row == visual left-hand side, 0th column == visual bottom
+            transpose(img, img);
+            flip(img, img, 0); //flip vertically
+            break;
+        default:
+            //by default the image read has normal (JPEG_ORIENTATION_TL) orientation
+            break;
+    }
+}
+
 /***************************************************************************
  * following code is for supporting MJPEG image files
  * based on a message of Laurent Pinchart on the video4linux mailing list
@@ -472,8 +526,10 @@ bool  JpegDecoder::readData( Mat& img )
                         icvCvt_CMYK2Gray_8u_C4C1R( buffer[0], 0, data, 0, cvSize(m_width,1) );
                 }
             }
+
             result = true;
             jpeg_finish_decompress( cinfo );
+            setOrientation( img );
         }
     }
 

modules/imgcodecs/src/grfmt_jpeg.hpp

@@ -70,6 +70,12 @@ protected:
 
     FILE* m_f;
     void* m_state;
+
+private:
+    //Support for handling exif orientation tag in Jpeg file
+    int m_orientation;
+    int getOrientation();
+    void setOrientation(Mat& img);
 };
 
 

modules/imgcodecs/src/jpeg_exif.cpp

+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+//  By downloading, copying, installing or using the software you agree to this license.
+//  If you do not agree to this license, do not download, install,
+//  copy or use the software.
+//
+//
+//                           License Agreement
+//                For Open Source Computer Vision Library
+//
+// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
+// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+//   * Redistribution's of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//
+//   * Redistribution's in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//
+//   * The name of the copyright holders may not be used to endorse or promote products
+//     derived from this software without specific prior written permission.
+//
+// This software is provided by the copyright holders and contributors "as is" and
+// any express or implied warranties, including, but not limited to, the implied
+// warranties of merchantability and fitness for a particular purpose are disclaimed.
+// In no event shall the Intel Corporation or contributors be liable for any direct,
+// indirect, incidental, special, exemplary, or consequential damages
+// (including, but not limited to, procurement of substitute goods or services;
+// loss of use, data, or profits; or business interruption) however caused
+// and on any theory of liability, whether in contract, strict liability,
+// or tort (including negligence or otherwise) arising in any way out of
+// the use of this software, even if advised of the possibility of such damage.
+//
+//M*/
+
+#include "jpeg_exif.hpp"
+
+namespace cv
+{
+
+/**
+ * @brief ExifReader constructor
+ */
+ExifReader::ExifReader(std::string filename) : m_filename(filename)
+{
+}
+
+/**
+ * @brief ExifReader destructor
+ */
+ExifReader::~ExifReader()
+{
+}
+
+/**
+ * @brief Parsing the jpeg file and prepare (internally) exif directory structure
+ * @return  true if parsing was successful and exif information exists in JpegReader object
+ *          false in case of unsuccessful parsing
+ */
+bool ExifReader::parse()
+{
+    m_exif = getExif();
+    if( !m_exif.empty() )
+    {
+        return true;
+    }
+    return false;
+}
+
+
+/**
+ *  @brief Get tag value by tag number
+ *
+ *  @param [in] tag The tag number
+ *
+ *  @return ExifEntru_t structure. Caller has to know what tag it calls in order to extract proper field from the structure ExifEntry_t
+ *
+ */
+ExifEntry_t ExifReader::getTag(const ExifTagName tag)
+{
+    ExifEntry_t entry;
+    std::map<int, ExifEntry_t>::iterator it = m_exif.find(tag);
+
+    if( it != m_exif.end() )
+    {
+        entry = it->second;
+    }
+    return entry;
+}
+
+
+/**
+ * @brief Get exif directory structure contained in jpeg file (if any)
+ *          This is internal function and is not exposed to client
+ *
+ *  @return Map where key is tag number and value is ExifEntry_t structure
+ */
+std::map<int, ExifEntry_t > ExifReader::getExif()
+{
+    const size_t markerSize = 2;
+    const size_t offsetToTiffHeader = 6; //bytes from Exif size field to the first TIFF header
+    unsigned char appMarker[markerSize];
+    m_exif.erase( m_exif.begin(), m_exif.end() );
+
+    size_t count;
+
+    FILE* f = fopen( m_filename.c_str(), "rb" );
+
+    if( !f )
+    {
+        return m_exif; //Until this moment the map is empty
+    }
+
+    bool exifFound = false;
+    while( ( !feof( f ) ) && !exifFound )
+    {
+        count = fread( appMarker, sizeof(unsigned char), markerSize, f );
+        if( count < markerSize )
+        {
+            break;
+        }
+        unsigned char marker = appMarker[1];
+        size_t bytesToSkip;
+        size_t exifSize;
+        switch( marker )
+        {
+            //For all the markers just skip bytes in file pointed by followed two bytes (field size)
+            case SOF0: case SOF2: case DHT: case DQT: case DRI: case SOS:
+            case RST0: case RST1: case RST2: case RST3: case RST4: case RST5: case RST6: case RST7:
+            case APP0: case APP2: case APP3: case APP4: case APP5: case APP6: case APP7: case APP8:
+            case APP9: case APP10: case APP11: case APP12: case APP13: case APP14: case APP15:
+            case COM:
+                bytesToSkip = getFieldSize( f );
+                fseek( f, static_cast<long>( bytesToSkip - markerSize ), SEEK_CUR );
+                break;
+
+            //SOI and EOI don't have the size field after the marker
+            case SOI: case EOI:
+                break;
+
+            case APP1: //actual Exif Marker
+                exifSize = getFieldSize(f);
+                m_data.resize( exifSize - offsetToTiffHeader );
+                fseek(f, static_cast<long>( offsetToTiffHeader ), SEEK_CUR);
+                count = fread( &m_data[0], sizeof( unsigned char ), exifSize - offsetToTiffHeader, f );
+                exifFound = true;
+                break;
+
+            default: //No other markers are expected according to standard. May be a signal of error
+                break;
+        }
+    }
+
+    fclose(f);
+
+    if( !exifFound )
+    {
+        return m_exif;
+    }
+
+    parseExif();
+
+    return m_exif;
+}
+
+/**
+ * @brief Get the size of exif field (required to properly ready whole exif from the file)
+ *          This is internal function and is not exposed to client
+ *
+ *  @return size of exif field in the file
+ */
+size_t ExifReader::getFieldSize (FILE* f) const
+{
+    unsigned char fieldSize[2];
+    size_t count = fread ( fieldSize, sizeof( char ), 2, f );
+    if (count < 2)
+    {
+        return 0;
+    }
+    return ( fieldSize[0] << 8 ) + fieldSize[1];
+}
+
+/**
+ * @brief Filling m_exif member with exif directory elements
+ *          This is internal function and is not exposed to client
+ *
+ *  @return The function doesn't return any value. In case of unsiccessful parsing
+ *      the m_exif member is not filled up
+ */
+void ExifReader::parseExif()
+{
+    m_format = getFormat();
+
+    if( !checkTagMark() )
+    {
+        return;
+    }
+
+    uint32_t offset = getStartOffset();
+
+    size_t numEntry = getNumDirEntry();
+
+    offset += 2; //go to start of tag fields
+
+    for( size_t entry = 0; entry < numEntry; entry++ )
+    {
+        ExifEntry_t exifEntry = parseExifEntry( offset );
+        m_exif.insert( std::make_pair( exifEntry.tag, exifEntry ) );
+        offset += tiffFieldSize;
+    }
+}
+
+/**
+ * @brief Get endianness of exif information
+ *          This is internal function and is not exposed to client
+ *
+ * @return INTEL, MOTO or NONE
+ */
+Endianess_t ExifReader::getFormat() const
+{
+    if( m_data[0] != m_data[1] )
+    {
+        return NONE;
+    }
+
+    if( m_data[0] == 'I' )
+    {
+        return INTEL;
+    }
+
+    if( m_data[0] == 'M' )
+    {
+        return MOTO;
+    }
+
+    return NONE;
+}
+
+/**
+ * @brief Checking whether Tag Mark (0x002A) correspond to one contained in the Jpeg file
+ *          This is internal function and is not exposed to client
+ *
+ * @return true if tag mark equals 0x002A, false otherwise
+ */
+bool ExifReader::checkTagMark() const
+{
+    uint16_t tagMark = getU16( 2 );
+
+    if( tagMark != tagMarkRequired )
+    {
+        return false;
+    }
+    return true;
+}
+
+/**
+ * @brief The utility function for extracting actual offset exif IFD0 info is started from
+ *          This is internal function and is not exposed to client
+ *
+ * @return offset of IFD0 field
+ */
+uint32_t ExifReader::getStartOffset() const
+{
+    return getU32( 4 );
+}
+
+/**
+ * @brief Get the number of Directory Entries in Jpeg file
+ *
+ * @return The number of directory entries
+ */
+size_t ExifReader::getNumDirEntry() const
+{
+    return getU16( offsetNumDir );
+}
+
+/**
+ * @brief Parsing particular entry in exif directory
+ *          This is internal function and is not exposed to client
+ *
+ *      Entries are divided into 12-bytes blocks each
+ *      Each block corresponds the following structure:
+ *
+ *      +------+-------------+-------------------+------------------------+
+ *      | Type | Data format | Num of components | Data or offset to data |
+ *      +======+=============+===================+========================+
+ *      | TTTT | ffff        | NNNNNNNN          | DDDDDDDD               |
+ *      +------+-------------+-------------------+------------------------+
+ *
+ *      Details can be found here: http://www.media.mit.edu/pia/Research/deepview/exif.html
+ *
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return ExifEntry_t structure which corresponds to particular entry
+ *
+ */
+ExifEntry_t ExifReader::parseExifEntry(const size_t offset)
+{
+    ExifEntry_t entry;
+    uint16_t tagNum = getExifTag( offset );
+    entry.tag = tagNum;
+
+    switch( tagNum )
+    {
+        case IMAGE_DESCRIPTION:
+            entry.field_str = getString( offset );
+            break;
+        case MAKE:
+            entry.field_str = getString( offset );
+            break;
+        case MODEL:
+            entry.field_str = getString( offset );
+            break;
+        case ORIENTATION:
+            entry.field_u16 = getOrientation( offset );
+            break;
+        case XRESOLUTION:
+            entry.field_u_rational = getResolution( offset );
+            break;
+        case YRESOLUTION:
+            entry.field_u_rational = getResolution( offset );
+            break;
+        case RESOLUTION_UNIT:
+            entry.field_u16 = getResolutionUnit( offset );
+            break;
+        case SOFTWARE:
+            entry.field_str = getString( offset );
+            break;
+        case DATE_TIME:
+            entry.field_str = getString( offset );
+            break;
+        case WHITE_POINT:
+            entry.field_u_rational = getWhitePoint( offset );
+            break;
+        case PRIMARY_CHROMATICIES:
+            entry.field_u_rational = getPrimaryChromaticies( offset );
+            break;
+        case Y_CB_CR_COEFFICIENTS:
+            entry.field_u_rational = getYCbCrCoeffs( offset );
+            break;
+        case Y_CB_CR_POSITIONING:
+            entry.field_u16 = getYCbCrPos( offset );
+            break;
+        case REFERENCE_BLACK_WHITE:
+            entry.field_u_rational = getRefBW( offset );
+            break;
+        case COPYRIGHT:
+            entry.field_str = getString( offset );
+            break;
+        case EXIF_OFFSET:
+            break;
+        default:
+            entry.tag = INVALID_TAG;
+            break;
+    }
+    return entry;
+}
+
+/**
+ * @brief Get tag number from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return tag number
+ */
+uint16_t ExifReader::getExifTag(const size_t offset) const
+{
+    return getU16( offset );
+}
+
+/**
+ * @brief Get string information from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return string value
+ */
+std::string ExifReader::getString(const size_t offset) const
+{
+    size_t size = getU32( offset + 4 );
+    size_t dataOffset = 8; // position of data in the field
+    if( size > maxDataSize )
+    {
+        dataOffset = getU32( offset + 8 );
+    }
+    std::vector<uint8_t>::const_iterator it = m_data.begin() + dataOffset;
+    std::string result( it, it + size ); //copy vector content into result
+
+    return result;
+}
+
+/**
+ * @brief Get unsigned short data from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return Unsigned short data
+ */
+uint16_t ExifReader::getU16(const size_t offset) const
+{
+    if( m_format == INTEL )
+    {
+        return m_data[offset] + ( m_data[offset + 1] << 8 );
+    }
+    return ( m_data[offset] << 8 ) + m_data[offset + 1];
+}
+
+/**
+ * @brief Get unsigned 32-bit data from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return Unsigned 32-bit data
+ */
+uint32_t ExifReader::getU32(const size_t offset) const
+{
+    if( m_format == INTEL )
+    {
+        return m_data[offset] +
+                ( m_data[offset + 1] << 8 ) +
+                ( m_data[offset + 2] << 16 ) +
+                ( m_data[offset + 3] << 24 );
+    }
+
+    return ( m_data[offset] << 24 ) +
+            ( m_data[offset + 1] << 16 ) +
+            ( m_data[offset + 2] << 8 ) +
+            m_data[offset + 3];
+}
+
+/**
+ * @brief Get unsigned rational data from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return Unsigned rational data
+ *
+ * "rational" means a fractional value, it contains 2 signed/unsigned long integer value,
+ *  and the first represents the numerator, the second, the denominator.
+ */
+u_rational_t ExifReader::getURational(const size_t offset) const
+{
+    u_rational_t result;
+    uint32_t numerator = getU32( offset );
+    uint32_t denominator = getU32( offset + 4 );
+
+    return std::make_pair( numerator, denominator );
+
+}
+
+/**
+ * @brief Get orientation information from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return orientation number
+ */
+uint16_t ExifReader::getOrientation(const size_t offset) const
+{
+    return getU16( offset + 8 );
+}
+
+/**
+ * @brief Get resolution information from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return resolution value
+ */
+std::vector<u_rational_t> ExifReader::getResolution(const size_t offset) const
+{
+    std::vector<u_rational_t> result;
+    uint32_t rationalOffset = getU32( offset + 8 );
+    result.push_back( getURational( rationalOffset ) );
+
+    return result;
+}
+
+/**
+ * @brief Get resolution unit from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return resolution unit value
+ */
+uint16_t ExifReader::getResolutionUnit(const size_t offset) const
+{
+    return getU16( offset + 8 );
+}
+
+/**
+ * @brief Get White Point information from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return White Point value
+ *
+ * If the image uses CIE Standard Illumination D65(known as international
+ * standard of 'daylight'), the values are '3127/10000,3290/10000'.
+ */
+std::vector<u_rational_t> ExifReader::getWhitePoint(const size_t offset) const
+{
+    std::vector<u_rational_t> result;
+    uint32_t rationalOffset = getU32( offset + 8 );
+    result.push_back( getURational( rationalOffset ) );
+    result.push_back( getURational( rationalOffset + 8 ) );
+
+    return result;
+}
+
+/**
+ * @brief Get Primary Chromaticies information from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return vector with primary chromaticies values
+ *
+ */
+std::vector<u_rational_t> ExifReader::getPrimaryChromaticies(const size_t offset) const
+{
+    std::vector<u_rational_t> result;
+    uint32_t rationalOffset = getU32( offset + 8 );
+    for( size_t i = 0; i < primaryChromaticiesComponents; i++ )
+    {
+        result.push_back( getURational( rationalOffset ) );
+        rationalOffset += 8;
+    }
+    return result;
+}
+
+/**
+ * @brief Get YCbCr Coefficients information from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return vector with YCbCr coefficients values
+ *
+ */
+std::vector<u_rational_t> ExifReader::getYCbCrCoeffs(const size_t offset) const
+{
+    std::vector<u_rational_t> result;
+    uint32_t rationalOffset = getU32( offset + 8 );
+    for( size_t i = 0; i < ycbcrCoeffs; i++ )
+    {
+        result.push_back( getURational( rationalOffset ) );
+        rationalOffset += 8;
+    }
+    return result;
+}
+
+/**
+ * @brief Get YCbCr Positioning information from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return vector with YCbCr positioning value
+ *
+ */
+uint16_t ExifReader::getYCbCrPos(const size_t offset) const
+{
+    return getU16( offset + 8 );
+}
+
+/**
+ * @brief Get Reference Black&White point information from raw exif data
+ *          This is internal function and is not exposed to client
+ * @param [in] offset Offset to entry in bytes inside raw exif data
+ * @return vector with reference BW points
+ *
+ * In case of YCbCr format, first 2 show black/white of Y, next 2 are Cb,
+ * last 2 are Cr. In case of RGB format, first 2 show black/white of R,
+ * next 2 are G, last 2 are B.
+ *
+ */
+std::vector<u_rational_t> ExifReader::getRefBW(const size_t offset) const
+{
+    const size_t rationalFieldSize = 8;
+    std::vector<u_rational_t> result;
+    uint32_t rationalOffset = getU32( offset + rationalFieldSize );
+    for( size_t i = 0; i < refBWComponents; i++ )
+    {
+        result.push_back( getURational( rationalOffset ) );
+        rationalOffset += rationalFieldSize;
+    }
+    return result;
+}
+
+} //namespace cv

modules/imgcodecs/src/jpeg_exif.hpp

+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+//  By downloading, copying, installing or using the software you agree to this license.
+//  If you do not agree to this license, do not download, install,
+//  copy or use the software.
+//
+//
+//                           License Agreement
+//                For Open Source Computer Vision Library
+//
+// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
+// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+//   * Redistribution's of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//
+//   * Redistribution's in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//
+//   * The name of the copyright holders may not be used to endorse or promote products
+//     derived from this software without specific prior written permission.
+//
+// This software is provided by the copyright holders and contributors "as is" and
+// any express or implied warranties, including, but not limited to, the implied
+// warranties of merchantability and fitness for a particular purpose are disclaimed.
+// In no event shall the Intel Corporation or contributors be liable for any direct,
+// indirect, incidental, special, exemplary, or consequential damages
+// (including, but not limited to, procurement of substitute goods or services;
+// loss of use, data, or profits; or business interruption) however caused
+// and on any theory of liability, whether in contract, strict liability,
+// or tort (including negligence or otherwise) arising in any way out of
+// the use of this software, even if advised of the possibility of such damage.
+//
+//M*/
+
+
+#ifndef _OPENCV_JPEG_EXIF_HPP_
+#define _OPENCV_JPEG_EXIF_HPP_
+
+#include <cstdio>
+#include <map>
+#include <utility>
+#include <algorithm>
+#include <stdint.h>
+#include <string>
+#include <vector>
+
+namespace cv
+{
+/**
+ * @brief Jpeg markers that can encounter in Jpeg file
+ */
+enum AppMarkerTypes
+{
+    SOI   = 0xD8, SOF0  = 0xC0, SOF2  = 0xC2, DHT   = 0xC4,
+    DQT   = 0xDB, DRI   = 0xDD, SOS   = 0xDA,
+
+    RST0  = 0xD0, RST1  = 0xD1, RST2  = 0xD2, RST3  = 0xD3,
+    RST4  = 0xD4, RST5  = 0xD5, RST6  = 0xD6, RST7  = 0xD7,
+
+    APP0  = 0xE0, APP1  = 0xE1, APP2  = 0xE2, APP3  = 0xE3,
+    APP4  = 0xE4, APP5  = 0xE5, APP6  = 0xE6, APP7  = 0xE7,
+    APP8  = 0xE8, APP9  = 0xE9, APP10 = 0xEA, APP11 = 0xEB,
+    APP12 = 0xEC, APP13 = 0xED, APP14 = 0xEE, APP15 = 0xEF,
+
+    COM   = 0xFE, EOI   = 0xD9
+};
+
+/**
+ * @brief Base Exif tags used by IFD0 (main image)
+ */
+enum ExifTagName
+{
+    IMAGE_DESCRIPTION       = 0x010E,   ///< Image Description: ASCII string
+    MAKE                    = 0x010F,   ///< Description of manufacturer: ASCII string
+    MODEL                   = 0x0110,   ///< Description of camera model: ASCII string
+    ORIENTATION             = 0x0112,   ///< Orientation of the image: unsigned short
+    XRESOLUTION             = 0x011A,   ///< Resolution of the image across X axis: unsigned rational
+    YRESOLUTION             = 0x011B,   ///< Resolution of the image across Y axis: unsigned rational
+    RESOLUTION_UNIT         = 0x0128,   ///< Resolution units. '1' no-unit, '2' inch, '3' centimeter
+    SOFTWARE                = 0x0131,   ///< Shows firmware(internal software of digicam) version number
+    DATE_TIME               = 0x0132,   ///< Date/Time of image was last modified
+    WHITE_POINT             = 0x013E,   ///< Chromaticity of white point of the image
+    PRIMARY_CHROMATICIES    = 0x013F,   ///< Chromaticity of the primaries of the image
+    Y_CB_CR_COEFFICIENTS    = 0x0211,   ///< constant to translate an image from YCbCr to RGB format
+    Y_CB_CR_POSITIONING     = 0x0213,   ///< Chroma sample point of subsampling pixel array
+    REFERENCE_BLACK_WHITE   = 0x0214,   ///< Reference value of black point/white point
+    COPYRIGHT               = 0x8298,   ///< Copyright information
+    EXIF_OFFSET             = 0x8769,   ///< Offset to Exif Sub IFD
+    INVALID_TAG             = 0xFFFF    ///< Shows that the tag was not recognized
+};
+
+enum Endianess_t
+{
+    INTEL = 0x49,
+    MOTO = 0x4D,
+    NONE = 0x00
+};
+
+typedef std::pair<uint32_t, uint32_t> u_rational_t;
+
+/**
+ * @brief Entry which contains possible values for different exif tags
+ */
+struct ExifEntry_t
+{
+    std::vector<u_rational_t> field_u_rational; ///< vector of rational fields
+    std::string field_str;                      ///< any kind of textual information
+
+    float  field_float;                         ///< Currently is not used
+    double field_double;                        ///< Currently is not used
+
+    uint32_t field_u32;                         ///< Unsigned 32-bit value
+    int32_t  field_s32;                         ///< Signed 32-bit value
+
+    uint16_t tag;                               ///< Tag number
+
+    uint16_t field_u16;                         ///< Unsigned 16-bit value
+    int16_t  field_s16;                         ///< Signed 16-bit value
+    uint8_t  field_u8;                          ///< Unsigned 8-bit value
+    int8_t   field_s8;                          ///< Signed 8-bit value
+};
+
+/**
+ * @brief Picture orientation which may be taken from JPEG's EXIF
+ *      Orientation usually matters when the picture is taken by
+ *      smartphone or other camera with orientation sensor support
+ *      Corresponds to EXIF 2.3 Specification
+ */
+enum JpegOrientation
+{
+    JPEG_ORIENTATION_TL = 1, ///< 0th row == visual top, 0th column == visual left-hand side
+    JPEG_ORIENTATION_TR = 2, ///< 0th row == visual top, 0th column == visual right-hand side
+    JPEG_ORIENTATION_BR = 3, ///< 0th row == visual bottom, 0th column == visual right-hand side
+    JPEG_ORIENTATION_BL = 4, ///< 0th row == visual bottom, 0th column == visual left-hand side
+    JPEG_ORIENTATION_LT = 5, ///< 0th row == visual left-hand side, 0th column == visual top
+    JPEG_ORIENTATION_RT = 6, ///< 0th row == visual right-hand side, 0th column == visual top
+    JPEG_ORIENTATION_RB = 7, ///< 0th row == visual right-hand side, 0th column == visual bottom
+    JPEG_ORIENTATION_LB = 8  ///< 0th row == visual left-hand side, 0th column == visual bottom
+};
+
+/**
+ * @brief Reading exif information from Jpeg file
+ *
+ * Usage example for getting the orientation of the image:
+ *
+ *      @code
+ *      ExifReader reader(fileName);
+ *      if( reader.parse() )
+ *      {
+ *          int orientation = reader.getTag(Orientation).field_u16;
+ *      }
+ *      @endcode
+ *
+ */
+class ExifReader
+{
+public:
+    /**
+     * @brief ExifReader constructor. Constructs an object of exif reader
+     *
+     * @param [in]filename The name of file to look exif info in
+     */
+    explicit ExifReader( std::string filename );
+    ~ExifReader();
+
+
+    /**
+     * @brief Parse the file with exif info
+     *
+     * @return true if parsing was successful and exif information exists in JpegReader object
+     */
+    bool parse();
+
+    /**
+     * @brief Get tag info by tag number
+     *
+     * @param [in] tag The tag number
+     * @return ExifEntru_t structure. Caller has to know what tag it calls in order to extract proper field from the structure ExifEntry_t
+     */
+    ExifEntry_t getTag( const ExifTagName tag );
+
+private:
+    std::string m_filename;
+    std::vector<unsigned char> m_data;
+    std::map<int, ExifEntry_t > m_exif;
+    Endianess_t m_format;
+
+    void parseExif();
+    bool checkTagMark() const;
+
+    size_t getFieldSize ( FILE* f ) const;
+    size_t getNumDirEntry() const;
+    uint32_t getStartOffset() const;
+    uint16_t getExifTag( const size_t offset ) const;
+    uint16_t getU16( const size_t offset ) const;
+    uint32_t getU32( const size_t offset ) const;
+    uint16_t getOrientation( const size_t offset ) const;
+    uint16_t getResolutionUnit( const size_t offset ) const;
+    uint16_t getYCbCrPos( const size_t offset ) const;
+
+    Endianess_t getFormat() const;
+
+    ExifEntry_t parseExifEntry( const size_t offset );
+
+    u_rational_t getURational( const size_t offset ) const;
+
+    std::map<int, ExifEntry_t > getExif();
+    std::string getString( const size_t offset ) const;
+    std::vector<u_rational_t> getResolution( const size_t offset ) const;
+    std::vector<u_rational_t> getWhitePoint( const size_t offset ) const;
+    std::vector<u_rational_t> getPrimaryChromaticies( const size_t offset ) const;
+    std::vector<u_rational_t> getYCbCrCoeffs( const size_t offset ) const;
+    std::vector<u_rational_t> getRefBW( const size_t offset ) const;
+
+private:
+    static const uint16_t tagMarkRequired = 0x2A;
+
+    //offset to the _number-of-directory-entry_ field
+    static const size_t offsetNumDir = 8;
+
+    //max size of data in tag.
+    //'DDDDDDDD' contains the value of that Tag. If its size is over 4bytes,
+    //'DDDDDDDD' contains the offset to data stored address.
+    static const size_t maxDataSize = 4;
+
+    //bytes per tag field
+    static const size_t tiffFieldSize = 12;
+
+    //number of primary chromaticies components
+    static const size_t primaryChromaticiesComponents = 6;
+
+    //number of YCbCr coefficients in field
+    static const size_t ycbcrCoeffs = 3;
+
+    //number of Reference Black&White components
+    static const size_t refBWComponents = 6;
+};
+
+
+
+}
+
+#endif /* JPEG_EXIF_HPP_ */

modules/imgcodecs/test/test_grfmt.cpp

@@ -43,6 +43,7 @@
 #include "test_precomp.hpp"
 
 #include <fstream>
+#include <sstream>
 
 using namespace cv;
 using namespace std;
@@ -118,6 +119,150 @@ TEST(Imgcodecs_imread, regression)
     }
 }
 
+template<class T>
+string to_string(T i)
+{
+    stringstream ss;
+    string s;
+    ss << i;
+    s = ss.str();
+
+    return s;
+}
+
+
+/**
+ * Test for check whether reading exif orientation tag was processed successfully or not
+ * The test info is the set of 8 images named testExifRotate_{1 to 8}.jpg
+ * The test image is the square 10x10 points divided by four sub-squares:
+ * (R corresponds to Red, G to Green, B to Blue, W to white)
+ * ---------             ---------
+ * | R | G |             | G | R |
+ * |-------| - (tag 1)   |-------| - (tag 2)
+ * | B | W |             | W | B |
+ * ---------             ---------
+ *
+ * ---------             ---------
+ * | W | B |             | B | W |
+ * |-------| - (tag 3)   |-------| - (tag 4)
+ * | G | R |             | R | G |
+ * ---------             ---------
+ *
+ * ---------             ---------
+ * | R | B |             | G | W |
+ * |-------| - (tag 5)   |-------| - (tag 6)
+ * | G | W |             | R | B |
+ * ---------             ---------
+ *
+ * ---------             ---------
+ * | W | G |             | B | R |
+ * |-------| - (tag 7)   |-------| - (tag 8)
+ * | B | R |             | W | G |
+ * ---------             ---------
+ *
+ *
+ * Every image contains exif field with orientation tag (0x112)
+ * After reading each image the corresponding matrix must be read as
+ * ---------
+ * | R | G |
+ * |-------|
+ * | B | W |
+ * ---------
+ *
+ */
+class CV_GrfmtJpegExifOrientationTest : public cvtest::BaseTest
+{
+public:
+    void run(int)
+    {
+        try
+        {
+            for( int i = 1; i <= 8; ++i)
+            {
+                string fileName = "readwrite/testExifOrientation_" + to_string(i) + ".jpg";
+                m_img = imread(string(ts->get_data_path()) + fileName);
+                if( !m_img.data )
+                {
+                    ts->set_failed_test_info(cvtest::TS::FAIL_MISSING_TEST_DATA);
+                }
+                ts->printf(cvtest::TS::LOG, "start  reading image\t%s\n", fileName.c_str());
+                if( !checkOrientation() )
+                {
+                    ts->set_failed_test_info(cvtest::TS::FAIL_MISMATCH);
+                }
+            }
+
+        }
+        catch(...)
+        {
+            ts->set_failed_test_info(cvtest::TS::FAIL_EXCEPTION);
+        }
+    }
+private:
+    bool checkOrientation();
+    Mat m_img;
+};
+
+
+bool CV_GrfmtJpegExifOrientationTest::checkOrientation()
+{
+    Vec3b vec;
+    int red = 0;
+    int green = 0;
+    int blue = 0;
+
+    const int colorThresholdHigh = 250;
+    const int colorThresholdLow = 5;
+
+    //Checking the first quadrant (with supposed red)
+    vec = m_img.at<Vec3b>(2, 2); //some point inside the square
+    red   = vec.val[2];
+    green = vec.val[1];
+    blue  = vec.val[0];
+
+    ts->printf(cvtest::TS::LOG, "RED QUADRANT:\n");
+    ts->printf(cvtest::TS::LOG, "Red calculated:\t\t%d\n", red);
+    ts->printf(cvtest::TS::LOG, "Green calculated:\t%d\n", green);
+    ts->printf(cvtest::TS::LOG, "Blue calculated:\t%d\n", blue);
+    if( red < colorThresholdHigh ) return false;
+    if( blue > colorThresholdLow ) return false;
+    if( green > colorThresholdLow ) return false;
+
+    //Checking the second quadrant (with supposed green)
+    vec = m_img.at<Vec3b>(2, 7);  //some point inside the square
+    red   = vec.val[2];
+    green = vec.val[1];
+    blue  = vec.val[0];
+    ts->printf(cvtest::TS::LOG, "GREEN QUADRANT:\n");
+    ts->printf(cvtest::TS::LOG, "Red calculated:\t\t%d\n", red);
+    ts->printf(cvtest::TS::LOG, "Green calculated:\t%d\n", green);
+    ts->printf(cvtest::TS::LOG, "Blue calculated:\t%d\n", blue);
+    if( green < colorThresholdHigh ) return false;
+    if( red > colorThresholdLow ) return false;
+    if( blue > colorThresholdLow ) return false;
+
+    //Checking the third quadrant (with supposed blue)
+    vec = m_img.at<Vec3b>(7, 2);  //some point inside the square
+    red   = vec.val[2];
+    green = vec.val[1];
+    blue  = vec.val[0];
+    ts->printf(cvtest::TS::LOG, "BLUE QUADRANT:\n");
+    ts->printf(cvtest::TS::LOG, "Red calculated:\t\t%d\n", red);
+    ts->printf(cvtest::TS::LOG, "Green calculated:\t%d\n", green);
+    ts->printf(cvtest::TS::LOG, "Blue calculated:\t%d\n", blue);
+    if( blue < colorThresholdHigh ) return false;
+    if( red > colorThresholdLow ) return false;
+    if( green > colorThresholdLow ) return false;
+
+    return true;
+}
+
+TEST(Imgcodecs_jpeg_exif, setOrientation)
+{
+    CV_GrfmtJpegExifOrientationTest test;
+    test.safe_run();
+}
+
 #ifdef HAVE_JASPER
 TEST(Imgcodecs_jasper, regression)
 {