How to crop a set of images based on another set of images

Question

I've accidentally switched the camera to reduced resolution and several hundreds of photographs have been stored this way.

There are RAWs for these so I can re-develop them to full resolution. Unfortunately, while original picture orientations are preserved, the in-camera JPEG cropping I've used is discarded and the JPEGs from RAWs are always in the sensor ratio 4:3 (or 3:4).

To sum up:

• There's one set of pictures (IMG1234.JPG - IMG2345.JPG) in the reduced resolution and correct aspect ratios 3:2, 2:3, 4:3 and 3:4.
• There's another set of pictures (IMG1234.JPG - IMG2345.JPG) in the full resolution and aspect ratios of 4:3 or 3:4.
• I need the target set of pictures in the full resolution in correct aspect ratios of 3:2, 2:3, 4:3 and 3:4.

What's the recommended tool/chain to accomplish that? Thanks.

Answer 1

I've developed a solution in .NET Core which I'm not going to accept (still waiting for a better answer).

The problem with this solution is that cropping isn't lossless (JPEGs are re-compressed) and ImageSharp somehow damages image metadata - the Date Taken time is displayed as 00:00 in XNView - I had to fix it using ExifTool by copying metadata from camera JPEGs.

Otherwise, it does what I need.

Images are placed in subfolders of a path:
/S - camera JPEGs with reduced resolution
/L - re-developed JPEGs from RAWs with full resolution
/T - target folder for cropped full resolution images

using System;
using System.IO;
using System.Linq;
using ImageSharp;
using SixLabors.Primitives;

namespace fix
{
    class Program
    {
        static void Main(string[] args)
        {
            var smalls = Directory.GetFiles("path/S").OrderBy(p => p);
            var tPath = "path/T/";            

            foreach (var path in smalls)
            {
                using (FileStream sStream = File.OpenRead(path))
                // change path to full resolution JPEGs from RAWs
                using (FileStream lStream = File.OpenRead(path.Replace("/S/", "/L/")))
                {
                    var small = Image.Load(sStream);
                    var large = Image.Load(lStream);
                    Rectangle rect = new Rectangle();

                    // image height of the reduced resolution image with in-camera cropping
                    // it's always height, the portrait (2:3) mode is only in EXIF
                    if (small.Height == 1360)
                    {
                        // crop rectangle on the full resolution image (see above)
                        rect = new Rectangle(0, 168, 4000, 2664);
                    }

                    // this file has been cropped
                    if (rect.Width != 0)
                    {
                        using (FileStream tStream = File.OpenWrite(string.Format("{0}{1}", tPath, Path.GetFileName(path))))
                        {
                            var encoder = new ImageSharp.Formats.JpegEncoder();
                            encoder.Quality = 98; // as desired
                            large.Crop(rect).Save(tStream, encoder);
                        }
                    }
                }
            }
        }           
    }
}