getedgehq/linkedin-media-prep

LinkedIn Media Prep

Prepare any image or video for LinkedIn with correct dimensions, cropping, and compression.

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Image Specs

Use Case	Dimensions	Ratio	Notes
Post (portrait, max feed space)	1080 × 1350	4:5	Default choice for photos
Post (landscape)	1200 × 627	1.91:1	Good for banners, screenshots
Post (square)	1080 × 1080	1:1	Safe universal choice
Post (4:3)	1440 × 1080	4:3	Good for camera-native photos
Profile photo	400 × 400 min	1:1	Recommend 800 × 800
Cover photo	1584 × 396	4:1
Article featured	1200 × 627	1.91:1
Max file size	8 MB	—	Target < 1 MB for fast upload
Formats	JPEG, PNG, GIF	—	JPEG preferred for photos

Video Specs

Use Case	Dimensions	Ratio	Notes
Post (square)	1080 × 1080	1:1	Safe universal choice
Post (landscape)	1920 × 1080	16:9	Standard feed video
Post (vertical)	1080 × 1920	9:16	Mobile/Reels-style; pad if source is not 9:16
Max file size	5 GB	—	Target < 200 MB for fast upload
Max duration	30 minutes	—	3 seconds minimum
Formats	MP4 (H.264 + AAC)	—	MP4 required for best compatibility
Frame rate	30 fps	—	Match source or standardise to 30 fps
Pixel format	yuv420p	—	Required for broad playback support

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Image Workflow

1. Inspect source

sips -g pixelWidth -g pixelHeight "<input>"
ls -lh "<input>"

2. Fix EXIF orientation (if needed)

iPhone and mobile photos often store portrait images with an EXIF orientation tag rather than rotated pixels. ImageMagick usually respects this automatically, but if the image appears sideways after conversion you can force it upright before cropping.

magick "<input>" -auto-orient "<input>-upright.png"

Use the upright version as your working copy for cropping.

3. Convert to editable format

If source is HEIC or other non-PNG:

sips -s format png "<input>" --out "<input>.png"

Use the PNG as the working copy for cropping.

4. Crop (iterative with user)

First crop: center, choose dimensions based on target ratio.

For a 4:5 portrait post from a portrait photo:

• Crop width = full width of image
• Crop height = width × 5 / 4
• Y-offset = (original_height − crop_height) / 2

Example for 3024 × 4032 source:

magick "source.png" -crop 3024x3780+0+126 "cropped.png"

Iterative adjustments:

• "More zoomed in" → reduce crop WxH (e.g. 2000×2500 instead of 3024×3780). Keep same ratio.
• "Too much space at top" → increase Y-offset (shift crop down).
• "Too much space at bottom" → decrease Y-offset (shift crop up).
• "Need wider/narrower" → adjust W and H maintaining ratio.

Crop formula:

magick "source.png" -crop <W>x<H>+<X>+<Y> "cropped.png"
# X = (original_width − W) / 2  (centered)
# Y = adjust based on subject position

5. Resize & compress for LinkedIn

magick "cropped.png" -resize 1080x1350 -quality 85 "<name>-linkedin.jpg"

For profile photos:

magick "cropped.png" -resize 800x800 -quality 85 "<name>-linkedin-profile.jpg"

For cover photos:

magick "cropped.png" -resize 1584x396 -quality 85 "<name>-linkedin-cover.jpg"

For 4:3 posts:

magick "source.png" -resize 1440x1080 -quality 85 "<name>-linkedin-4by3.jpg"

6. Verify output

ls -lh "<output>.jpg"
sips -g pixelWidth -g pixelHeight "<output>.jpg"

Ensure:

• Dimensions match target
• File size < 8 MB (preferably < 1 MB)
• Quality is acceptable

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Which video format should I choose?

Source orientation	Your goal	Recommended target
Portrait (phone video)	Maximum mobile feed space	Vertical 1080×1920 (pad with black if source is 3:4 or 4:5)
Portrait (phone video)	Safe universal compatibility	Square 1080×1080 (centre-crop)
Landscape (screen-recording, camera)	Standard feed video	Landscape 1920×1080
Landscape	Safe universal compatibility	Square 1080×1080 (centre-crop)
Not sure	—	Square 1080×1080

Rule of thumb: Square works everywhere. Vertical gets the most mobile screen real estate but can letterbox on desktop. Landscape is best for demos, interviews, and cinematic content.

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Video Workflow

1. Inspect source

ffprobe -v error -select_streams v:0 \
  -show_entries stream=width,height,avg_frame_rate,duration,bit_rate \
  -show_entries format=duration,size,bit_rate \
  -of csv=p=0 "<input>"

Also check for rotation metadata:

ffprobe -v error -select_streams v:0 -show_entries stream_side_data=display_matrix \
  -of default=nk=1:nw=1 "<input>"

2. Handle rotation (iPhone / mobile sources)

Mobile videos often store frames in landscape with a rotation tag. Apply transpose in the filter chain before cropping/scaling.

Display Matrix	Transpose value	Meaning
-90° (270°)	1	90° clockwise
+90°	2	90° counter-clockwise
180°	3	180°
No rotation	omit	—

3. Choose target and build filter chain

Square (1080×1080) — centre-crop after rotation:

transpose=1,crop=1080:1080:(in_w-1080)/2:(in_h-1080)/2,format=yuv420p

Landscape (1920×1080) — scale to fit then pad, or centre-crop:

transpose=1,scale=1920:-2,pad=1920:1080:(ow-iw)/2:(oh-ih)/2:black,format=yuv420p

Vertical (1080×1920) — scale to width then pad top/bottom:

transpose=1,scale=1080:-2,pad=1080:1920:(ow-iw)/2:(oh-ih)/2:black,format=yuv420p

If the source aspect ratio already matches the target, you can omit pad and just scale=1080:1080 or scale=1920:1080.

4. Common one-liner (portrait iPhone → square)

The most frequent request: a portrait iPhone video converted to a LinkedIn-ready square MP4.

ffmpeg -y -i "IMG_xxxx.MOV" \
  -vf "transpose=1,crop=1080:1080:(in_w-1080)/2:(in_h-1080)/2,format=yuv420p" \
  -c:v libx264 -profile:v main -level 4.2 -preset medium -crf 23 -r 30 \
  -c:a aac -b:a 128k -movflags +faststart \
  "output_linkedin_square.mp4"

Swap transpose=1 for the correct rotation value from Step 2, or omit transpose=1, if the source has no rotation metadata.

5. Transcode

ffmpeg -y -i "<input>" \
  -vf "<filter_chain>" \
  -c:v libx264 -profile:v main -level 4.2 -preset medium -crf 23 -r 30 \
  -c:a aac -b:a 128k \
  -movflags +faststart \
  "<output>.mp4"

Parameter notes:

• -profile:v main -level 4.2 — broad device compatibility
• -crf 23 — good quality / size balance (lower = higher quality)
• -r 30 — standardise frame rate
• -movflags +faststart — moov atom at beginning for web streaming

6. Verify output

ls -lh "<output>.mp4"
ffprobe -v error -select_streams v:0 \
  -show_entries stream=width,height,avg_frame_rate,duration,bit_rate \
  -show_entries format=duration,size,bit_rate \
  -of csv=p=0 "<output>.mp4"

Ensure:

• Dimensions match target
• File size reasonable for upload (< 200 MB ideally)
• No rotation metadata remains (players should not rotate it again)

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Tools

• Images: Prefer magick (ImageMagick 7) or convert (ImageMagick 6). Fallback to sips on macOS for basic format conversion. Install via brew install imagemagick.
• Videos: ffmpeg + ffprobe. Install via brew install ffmpeg.