Cloudinary Media Hosting

Cloudinary provides image and video hosting with CDN delivery, automatic optimization, and on-the-fly transformations.

When to Use

• Upload images with automatic optimization
• Upload videos with CDN delivery
• Get CDN-delivered media URLs
• Apply transformations (resize, crop, format conversion)
• Concatenate/splice multiple videos
• Host media for production applications

Prerequisites

Set the following environment variables:

export CLOUDINARY_CLOUD_NAME=your_cloud_name
export CLOUDINARY_API_KEY=your_api_key
export CLOUDINARY_API_SECRET=your_api_secret

Get credentials from: https://console.cloudinary.com/settings/api-keys

Important: When using $VAR in a command that pipes to another command, wrap the command containing $VAR in bash -c '...'. Due to a Claude Code bug, environment variables are silently cleared when pipes are used directly.

bash -c 'curl -s "https://api.example.com" -H "Authorization: Bearer $API_KEY"' | jq .

How to Use

Method 1: Unsigned Upload (Simpler)

First, create an unsigned upload preset in Cloudinary Console: Settings > Upload > Upload presets > Add upload preset > Signing Mode: Unsigned

curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/image/upload" -F "file=@/path/to/image.png" -F "upload_preset=your_preset_name"

Method 2: Signed Upload

Generate signature and upload:

# Generate timestamp
TIMESTAMP=$(date +%s)

# Generate signature (alphabetical order of params)
SIGNATURE=$(echo -n "timestamp=$TIMESTAMP$CLOUDINARY_API_SECRET" | sha1sum | cut -d' ' -f1)

# Upload
curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/image/upload" -F "file=@/path/to/image.png" -F "api_key=$CLOUDINARY_API_KEY" -F "timestamp=$TIMESTAMP" -F "signature=$SIGNATURE"

Upload from URL

TIMESTAMP=$(date +%s)
SIGNATURE=$(echo -n "timestamp=$TIMESTAMP$CLOUDINARY_API_SECRET" | sha1sum | cut -d' ' -f1)

curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/image/upload" -F "file=https://example.com/image.png" -F "api_key=$CLOUDINARY_API_KEY" -F "timestamp=$TIMESTAMP" -F "signature=$SIGNATURE"

Upload Video

TIMESTAMP=$(date +%s)
SIGNATURE=$(echo -n "timestamp=$TIMESTAMP$CLOUDINARY_API_SECRET" | sha1sum | cut -d' ' -f1)

curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/video/upload" -F "file=@/path/to/video.mp4" -F "api_key=$CLOUDINARY_API_KEY" -F "timestamp=$TIMESTAMP" -F "signature=$SIGNATURE"

Upload Video with Custom Public ID

TIMESTAMP=$(date +%s)
PUBLIC_ID="my-videos/clip1"
SIGNATURE=$(echo -n "public_id=$PUBLIC_ID&timestamp=$TIMESTAMP$CLOUDINARY_API_SECRET" | sha1sum | cut -d' ' -f1)

curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/video/upload" -F "file=@/path/to/video.mp4" -F "public_id=$PUBLIC_ID" -F "api_key=$CLOUDINARY_API_KEY" -F "timestamp=$TIMESTAMP" -F "signature=$SIGNATURE"

Upload Video from URL

TIMESTAMP=$(date +%s)
PUBLIC_ID="my-videos/clip1"
SIGNATURE=$(echo -n "public_id=$PUBLIC_ID&timestamp=$TIMESTAMP$CLOUDINARY_API_SECRET" | sha1sum | cut -d' ' -f1)

curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/video/upload" -F "file=https://example.com/video.mp4" -F "public_id=$PUBLIC_ID" -F "api_key=$CLOUDINARY_API_KEY" -F "timestamp=$TIMESTAMP" -F "signature=$SIGNATURE"

With Custom Public ID

TIMESTAMP=$(date +%s)
PUBLIC_ID="my-folder/my-image"
SIGNATURE=$(echo -n "public_id=$PUBLIC_ID&timestamp=$TIMESTAMP$CLOUDINARY_API_SECRET" | sha1sum | cut -d' ' -f1)

curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/image/upload" -F "file=@/path/to/image.png" -F "public_id=$PUBLIC_ID" -F "api_key=$CLOUDINARY_API_KEY" -F "timestamp=$TIMESTAMP" -F "signature=$SIGNATURE"

Response

{
  "public_id": "sample",
  "secure_url": "https://res.cloudinary.com/demo/image/upload/v1234567890/sample.png",
  "url": "http://res.cloudinary.com/demo/image/upload/v1234567890/sample.png",
  "format": "png",
  "width": 800,
  "height": 600
}

Key field: secure_url - Use this in Markdown: ![img](https://res.cloudinary.com/...)

URL Transformations

Cloudinary URLs support on-the-fly transformations:

https://res.cloudinary.com/{cloud_name}/image/upload/{transformations}/{public_id}.{format}

Examples:

# Resize to 300x200
.../image/upload/w_300,h_200/sample.png

# Auto format and quality
.../image/upload/f_auto,q_auto/sample.png

# Crop to square
.../image/upload/w_200,h_200,c_fill/sample.png

# Combine transformations
.../image/upload/w_400,h_300,c_fill,f_auto,q_auto/sample.png

Video Concatenation (Splice)

Concatenate videos using URL transformations with l_video: (overlay) and fl_splice flag.

Basic Concatenation

Append clip2 to the end of clip1:

https://res.cloudinary.com/{cloud_name}/video/upload/l_video:clip2,fl_splice/fl_layer_apply/clip1.mp4

Concatenate Multiple Videos

Append clip2 and clip3 to clip1:

https://res.cloudinary.com/{cloud_name}/video/upload/l_video:clip2,fl_splice/fl_layer_apply/l_video:clip3,fl_splice/fl_layer_apply/clip1.mp4

With Uniform Size

Resize all videos to same dimensions:

https://res.cloudinary.com/{cloud_name}/video/upload/w_640,h_360,c_fill/l_video:clip2,fl_splice,w_640,h_360,c_fill/fl_layer_apply/clip1.mp4

With Fade Transition

Add fade out (-1000ms) on first video and fade in (1000ms) on second:

https://res.cloudinary.com/{cloud_name}/video/upload/w_640,h_360,c_fill,e_fade:-1000/l_video:clip2,fl_splice,e_fade:1000,w_640,h_360,c_fill/fl_layer_apply/clip1.mp4

Add Image as Intro (3 seconds)

Prepend an image as intro:

https://res.cloudinary.com/{cloud_name}/video/upload/l_intro_image,fl_splice,du_3/so_0,fl_layer_apply/clip1.mp4

Limitations

• URL length limit (~2000 chars) restricts number of videos
• First request triggers server-side processing (slow)
• For many videos (10+), consider using ffmpeg or dedicated video APIs

Delete Media

TIMESTAMP=$(date +%s)
PUBLIC_ID="your_public_id"
SIGNATURE=$(echo -n "public_id=$PUBLIC_ID&timestamp=$TIMESTAMP$CLOUDINARY_API_SECRET" | sha1sum | cut -d' ' -f1)

# Delete image
curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/image/destroy" -F "public_id=$PUBLIC_ID" -F "api_key=$CLOUDINARY_API_KEY" -F "timestamp=$TIMESTAMP" -F "signature=$SIGNATURE"

# Delete video
curl -X POST "https://api.cloudinary.com/v1_1/$CLOUDINARY_CLOUD_NAME/video/destroy" -F "public_id=$PUBLIC_ID" -F "api_key=$CLOUDINARY_API_KEY" -F "timestamp=$TIMESTAMP" -F "signature=$SIGNATURE"

Free Tier Limits

• 25 credits/month
• ~25,000 transformations or ~25GB storage/bandwidth
• Sufficient for personal projects

Guidelines

1. Use unsigned presets for simpler uploads when security isn't critical
2. Signature order: Parameters must be alphabetically sorted when generating signature
3. Auto optimization: Add f_auto,q_auto to URLs for automatic format/quality
4. Folders: Use public_id="folder/subfolder/name" to organize media
5. Video concatenation: Keep URLs short; for 10+ videos use external tools

API Reference

• Image Upload: https://cloudinary.com/documentation/image_upload_api_reference
• Video Upload: https://cloudinary.com/documentation/video_upload_api_reference
• Video Concatenation: https://cloudinary.com/documentation/video_trimming_and_concatenating
• Console: https://console.cloudinary.com/
• Transformation Reference: https://cloudinary.com/documentation/transformation_reference