Video Frame Delta Hider

Frame delta steganography is a technique for hiding secret data inside digital video by modifying the pixel differences between consecutive frames. Rather than modifying individual frames directly, it computes the delta (difference) between each frame and its predecessor, then embeds message bits into the least significant bits of these delta values. Because human vision is more sensitive to static patterns than to small changes in moving regions, modifications to frame deltas are significantly harder to detect than per-frame LSB modifications.

Our Video Frame Delta Hider implements this technique using the browser's Canvas API to capture and process video frames. It supports configurable LSB bit depth (1-4 bits) for balancing stealth vs capacity, adjustable frame spacing to distribute data across the video timeline, and both Hide and Extract modes for complete steganography workflows. All processing runs locally in your browser with no video uploads to any server.

1. 1. Video Loading & Frame Capture: Upload a video file (MP4, WebM, MKV) which is loaded into a hidden video element. The tool reads video metadata including dimensions, duration, and estimated frame count. You select the LSB bit depth and frame step interval to control how data is distributed across the video. A capacity calculator shows how many bytes can be stored per frame.
2. 2. Delta-Based Encoding: In Hide mode, your secret message is converted to a bit sequence with a 32-bit length prefix. The tool seeks to each target frame position, captures the frame to a canvas, and modifies the RGB pixel values' least significant bits to encode the message data. Because the modifications target pixel values directly (which form the basis of inter-frame deltas), the resulting frame differences carry the hidden information while remaining imperceptible during playback.
3. 3. Video Export & Extraction: After encoding, the modified frames are reconstructed into a playable video using CanvasCaptureMediaStream and the MediaRecorder API, producing a WebM file that can be downloaded and shared. In Extract mode, the tool scans the video frames, reads the LSBs of pixel values across the specified frame range, reconstructs the bit sequence, and decodes the hidden message. The extracted text is displayed with copy functionality.

• LSB Bit Depth: Controls how many bits per color channel are modified. 1 LSB provides maximum stealth with 3 bits per pixel (one per RGB channel). 4 LSBs provides 12 bits per pixel for higher capacity but increases statistical detectability. The tool supports 1, 2, 3, and 4 LSB depths, letting you trade off capacity vs stealth.
• Frame Step / Spacing: Determines how many frames apart the modified frames are. Using every frame (step=1) distributes data evenly but may create a detectable temporal pattern. Using spaced frames (step=5, 10, or 30) makes the hidden data harder to detect statistically while reducing total capacity. Spaced frames also speed up processing for longer videos.
• Delta vs Direct Frame LSB: Direct frame LSB modifies each frame independently. Frame delta steganography is conceptually similar but emphasizes modification of inter-frame differences. Since both techniques modify pixel values in the spatial domain, the practical implementation uses the same LSB modification approach but with an emphasis on distributing changes across frame transitions where human perception is less sensitive.
• Capacity Estimation: The tool calculates available capacity based on video resolution (width x height), frame count, bit depth, and the 4-byte length header required per frame. A 1080p video at 30fps with 1 LSB provides approximately 1.2 MB of hidden data capacity per minute of video, while 4 LSBs provides about 4.7 MB per minute.

The Video Frame Delta Hider is 100% free with no signup required. All video processing is performedlocally in your browser using the Canvas API and MediaRecorder - your video files, secret messages, and stego outputsnever leave your device. There areno usage limits or rate caps. The tool supports MP4, WebM, and MKV video formats, provides configurable bit depth and frame spacing, generates downloadable WebM stego videos with playable previews, and supports both hiding and extraction of messages. Use it as many times as you need for covert communication, watermarking, education, or research.