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Overview

fix_jp2_v2 is a specialized utility that corrects malformed GeoTIFF projection metadata in HiRISE (High Resolution Imaging Science Experiment) JPEG2000 files. It specifically fixes Equirectangular projections that were incorrectly encoded with CenterLatGeoKey instead of StandardParallel1GeoKey.
This tool performs in-place binary editing of GeoJP2 headers without decompressing or recompressing the imagery, making it extremely fast.

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The Problem

Historically, some HiRISE GeoJP2 files were generated with incorrect GeoTIFF projection parameters for Equirectangular projections. According to the GeoTIFF specification:
  • Incorrect: Using CenterLatGeoKey (tag 3089)
  • Correct: Using StandardParallel1GeoKey (tag 3078)
This discrepancy caused projection misinterpretation in GDAL and other GIS software.
As of version 2 (January 2023), this tool will not modify files that already have correct StandardParallel1GeoKey tags. The HiRISE team has updated their processing pipeline.
GDAL Ticket #2706

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Installation

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Pre-compiled Windows Executable

A Windows executable (fix_jp2_v2.exe) is included in the repository: 
~/workspace/source/HiRISE_fix_jp2/fix_jp2_v2.exe
Use from any Windows command-line terminal (cmd, PowerShell).

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Compile from Source

On Linux, macOS, or Windows with GCC: 
g++ -o fix_jp2_v2 fix_jp2_v2.cpp
No external libraries required - uses only standard C/C++ libraries.

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Usage

fix_jp2_v2 HiRISE_targetfile.jp2

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Parameters

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targetfile.jp2
string
required
Path to the HiRISE JPEG2000 file to fix. The file is modified in-place.

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How It Works

1

Locate GeoTIFF Header

Scans the first 10KB of the JP2 file for the embedded TIFF header within the UUID box.
2

Find GeoKey Directory

Locates the GEOKEYDIRECTORY tag (34735) containing projection parameters.
3

Check for Existing Fix

Searches for StandardParallel1GeoKey (3078). If found, exits without changes.
4

Locate CenterLatGeoKey

Finds the incorrect CenterLatGeoKey (3089) tag.
5

Binary Edit

Replaces tag 3089 bytes with 3078 bytes in the file header.
6

Verify and Report

Confirms successful write and reports “Success, file updated.”

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Examples

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Fix Single File

fix_jp2_v2 ESP_012345_1234_RED.JP2
Output (if needs fixing): 
Success, file updated.
Output (if already correct): 
WARNING: tag (3078 / StdParallel1GeoKey already exists). No change will be made - exiting.

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Batch Processing

Linux/macOS: 
for file in *.JP2; do
  echo "Processing $file"
  fix_jp2_v2 "$file"
done
Windows (PowerShell): 
Get-ChildItem *.JP2 | ForEach-Object {
  Write-Host "Processing $_"
  .\fix_jp2_v2.exe $_.FullName
}

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Verify Fix with GDAL

Before: 
gdalinfo ESP_012345_1234_RED.JP2 | grep -A 5 "PROJECTION"
After: 
gdalinfo ESP_012345_1234_RED.JP2 | grep -A 5 "PROJECTION"
Look for standard_parallel_1 parameter in the output.

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Technical Details

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File Format Constraints

Little-Endian Only: This tool only works on little-endian TIFF/GeoTIFF data. Big-endian files are detected but may not be processed correctly.
  • GeoTIFF data must be within the first 10KB of the JP2 file
  • Does not validate that the file actually uses Equirectangular projection
  • Does not modify image data or recompress JPEG2000 stream

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What Gets Modified

Only 2 bytes in the GeoKey directory are changed: 
Tag 3089 (0x0C11) → Tag 3078 (0x0C06)
All other projection parameters (standard parallel value, central meridian, etc.) remain unchanged.

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Safety

Backup Recommended: While the tool only modifies 2 bytes, it’s good practice to keep backups of original files before batch processing.
The tool:
  • Opens files in read-write binary mode (rb+)
  • Only writes 2 bytes at the specific tag location
  • Does not modify files that already have correct tags
  • Exits with error if GeoTIFF structure is not found

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Error Messages

ErrorMeaningSolution
Failed to open fileFile not found or no read/write permissionsCheck path and permissions
Did not find TIFF headerNot a GeoJP2 file or GeoTIFF data not in first 10KBFile may not be a GeoJP2 or is corrupted
Failed to find GEOKEYDIRECTORY tagNo GeoTIFF projection infoFile lacks geospatial metadata
Unable to find target tag (3089 / CenterLat)Already uses correct tag or different projectionNo fix needed
StdParallel1GeoKey already existsFile already correctedNo action taken (v2 behavior)

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HiRISE Background

HiRISE (High Resolution Imaging Science Experiment) is a camera aboard NASA’s Mars Reconnaissance Orbiter that captures images at resolutions up to 25-30 cm/pixel.

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HiRISE Data Products

  • Observation IDs: ESP_######_#### or PSP_######_####
  • Standard Products: Red-band, color (IRB/RGB), and DTMs
  • Projections: Typically Equirectangular for regional maps
  • Formats: JPEG2000 for web distribution, ISIS cubes for processing

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When to Use This Tool

Use fix_jp2_v2 for:
  • Legacy HiRISE JP2 files (pre-2023) with projection issues
  • Downloaded JP2 files that GDAL reports incorrect projection
  • Files showing CenterLatGeoKey when StandardParallel1GeoKey is expected
Current HiRISE Data: Files processed after January 2023 by the HiRISE team should already have correct projection tags and won’t need fixing.

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Verification Script

Check if a file needs fixing: 
#!/bin/bash
# check_hirise_projection.sh

file="$1"
info=$(gdalinfo "$file" 2>&1)

if echo "$info" | grep -q "standard_parallel_1"; then
  echo "✓ $file: Projection is correct"
else
  echo "✗ $file: May need fixing"
fi
Usage: 
chmod +x check_hirise_projection.sh
./check_hirise_projection.sh ESP_012345_1234_RED.JP2

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Script Location

~/workspace/source/HiRISE_fix_jp2/fix_jp2_v2.cpp
~/workspace/source/HiRISE_fix_jp2/fix_jp2_v2.exe (Windows)

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Additional Resources

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Credits

Author: Frank Warmerdam (warmerdam@pobox.com)
v2 Update: Trent Hare (thare@usgs.gov) - January 2023 License: Public Domain
This tool is provided as-is for the planetary science community. Always validate outputs after processing.