FFMpeg - JPG/PNG images render in incorrect orientation in MP4 output file and can't be combined in same MP4 video

Question

I am a new user to FFMpeg.

I want a command-line that will create a basic slideshow MP4 video from a folder of JPG and/or PNG images. The images are sourced from either digital cameras/smartphones or scanned photos (typically 600 dpi).

I have been partially successful so far by creating an input text file with a list of the image filenames from the folder with a "duration 2" command after each "file" statement to introduce a 2 second delay between each image.

ffmpeg -hide_banner -f concat -safe 0 -i MQSS_test-ffmpeg.Txt -c:v libx264 -r 30 -pix_fmt yuv420p MQSS_test-ffmpeg.mp4

I have noticed two strange behaviors.

Behavior #1: Incorrect orientation

All images in the MP4 output file are rendered either in portrait or landscape orientation depending on the orientation of the first image. And because I have a mix of portrait and landscape images in the folder, the images that are rendered in the incorrect orientation are stretched or squashed. So if the first image is portrait, all images render as portrait. If the first image is landscape, all images are rendered as landscape.

Is there a way to get the images to render in their correct orientation?

Behavior #2: Can't mix image formats

I can't mix both JPG and PNG image files in the same input file. I receive several errors:

invalid data found when processing input can not process SOS before SOF, skipping unsupported coding type (ca)

However, if I separate the JPG and PNG files into separate JPG and PNG input files and run the separately, both image types render correctly.

Any ideas?

Answer 1

Is there a way to get the images to render in their correct orientation?

Example adapted from Resizing videos with ffmpeg to fit a specific size:

ffmpeg -framerate 1/2 -i %04d.jpg -filter_complex "scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720:-1:-1:color=black,format=yuv420p" -r 30 -movflags +faststart output.mp4

Also see image demuxer documentation.

I can't mix both JPG and PNG image files in the same input file.

• Convert them all to one file type before making a video.

• Or individually input each image and use the concat filter to concatenate them. This method would be tedious.

Answer 2

As far as I know, ffmpeg cannot use the EXIF Orientation tag to rotate the images accordingly. So you need to rotate the images first, before using ffmpeg to combine them into a slideshow.

To rotate JPEG images losslessly (without recompressing them) there are various tools like Xnview's nconvert, exiftran, and probably many others.

So for example, to rotate all "*.jpg" images in the current directory according to their Exif tag using exiftran :

exiftran -a -i -b *.jpg

The meaning of the flags used:

-a     Automatic (using exif orientation tag).
-i     Enable in-place editing of the images.
-b     Create a backup file when doing in-place editing 

After that, you can use ffmpeg with the options you need.