AVI to BMP Converter

How to Convert AVI to BMP Online

1. Upload Your AVI File: Drag and drop, or click "+ Add Files" to select one or more AVI clips. Batch is supported, and files process in your browser session — no account, no watermark.
2. Pick Frame Selection: Choose Specific Frame and enter a timestamp under Time (seconds) (decimals like 5.25 work) for a single still, or Multiple Screenshots to extract a sequence at intervals from every 0.1 seconds up to every 10 seconds.
3. Set Image Resolution and Quality (Optional): Under Image Resolution, keep the source dimensions, scale by Resolution Percentage, choose a Preset Resolutions value (144p through 4320p), or type exact Width x Height values. The Quality preset dropdown (Highest through Lowest) controls visual fidelity before encoding to bitmap; resolution is the dominant size lever because BMP is largely uncompressed.
4. Convert and Download: Click Convert. Single-frame jobs return one BMP; multi-screenshot jobs return a numbered sequence (image-0001.bmp, image-0002.bmp, ...) packaged for download.

Why Convert AVI to BMP?

AVI (Audio Video Interleave) is Microsoft's 1992 RIFF-based container that often holds DivX, Xvid, MJPEG, DV, or uncompressed video — common in older camcorder dumps, lab capture rigs, and legacy Windows software output. BMP (Windows Bitmap) is also a Microsoft format and stores pixel data with little or no compression at 1, 2, 4, 8, 16, 24, or 32 bits per pixel. Extracting AVI frames as BMP gives you raw, predictable, per-pixel image data that older Windows tools, embedded firmware loaders, and machine-vision pipelines can read directly.

• Legacy Windows imaging software — apps written against the GDI bitmap API (older medical viewers, industrial control panels, GIS plotters) often read BMP natively but choke on modern PNG/WebP/AVIF. Pulling stills from an archival AVI back out as BMP is the path of least resistance.
• Machine vision and LabVIEW — NI Vision, OpenCV, MATLAB, and similar toolchains accept BMP without a decode library, which keeps deterministic latency in real-time inspection loops where decoding JPEG or PNG would add jitter.
• Embedded systems and microcontroller displays — TFT/OLED splash screens, ATM panels, kiosk firmware, and ESP32/STM32 graphics demos commonly load 1-bit, 8-bit indexed, or 16-bit RGB565 BMPs straight from flash. Converting an AVI animation to a BMP frame sequence lets you script a slideshow for these targets.
• Forensic and scientific frame inspection — when chain-of-custody requires zero re-encoding artifacts after the original AVI capture, BMP preserves every pixel value exactly so subsequent measurements (line intensity, color sampling, motion delta) operate on untouched data.
• Texture sources for older 3D engines — DirectX 7/8/9 sample code, Quake-era engines, and many retro game frameworks load BMP textures by default. AVI cutscene captures convert cleanly into per-frame BMP texture sequences.
• Print-ready single frames — pulling one sharp frame from an AVI for a flyer, poster, or report avoids the lossy JPEG cycle that some print shops complain about.

AVI to BMP vs Other Frame-Extraction Targets

BMP Bit Depth and Color Palette Quick Guide

XConvert exposes 1-, 8-, and 16-bit depth options under Image Bit Depth, plus palette sizes from 2 to 256 colors under Image Color Palette Size when you pick an indexed mode.

Frequently Asked Questions

Why extract as BMP instead of PNG or JPG?

BMP stores pixels close to the wire format the source decoder produced — at 16, 24, or 32 bpp it skips compression entirely, which is what older Windows imaging libraries, machine-vision SDKs, and microcontroller graphics drivers expect. PNG is also lossless but applies DEFLATE compression that some embedded loaders cannot decode without an extra library; JPG is lossy and unacceptable when downstream analysis (forensics, science, vision) needs untouched pixel values.

How large will the BMP files be?

A 24-bit 1920x1080 BMP is roughly 6.2 MB (about 2.07 megapixels x 3 bytes plus a 54-byte header). A 4K (3840x2160) frame lands near 24 MB, and an 8K frame around 100 MB. Multi-frame extraction multiplies fast — 100 stills at 1080p is ~600 MB. Reduce Resolution Percentage to 50% to quarter the file size, switch to 8-bit indexed, or use AVI to PNG for a lossless-but-smaller option.

Which AVI codecs does the converter handle?

XConvert decodes AVI files carrying DivX, Xvid, MJPEG, MPEG-4 ASP, H.264-in-AVI, DV, Microsoft Video 1, Indeo, Cinepak, and uncompressed video. Per the AVI specification AVI is a RIFF container, so any common video codec inside the chunk structure should decode correctly.

Can I extract a frame at a specific timestamp?

Yes. Choose Specific Frame under Frame Selection and enter the timestamp in the Time (seconds) field. Decimal values are supported — 5.25 pulls the frame at 5 seconds 250 milliseconds, 12.033 lands near frame 361 in a 30 fps clip. The closest decoded frame to that time is returned.

How do I extract a sequence — say one BMP per second?

Pick Multiple Screenshots, then set the interval dropdown to 1 second (other choices range from 0.1 second to 10 seconds). The converter walks the AVI start to finish at that cadence and outputs a numbered BMP sequence. For frame-accurate per-frame export at the source rate, set the interval to match 1 / framerate (e.g., 0.033 s for 30 fps, 0.04 s for 25 fps).

Will the output BMPs work on legacy Windows XP / Windows 98 viewers?

24-bit and 8-bit indexed BMPs from XConvert are written with the standard BITMAPINFOHEADER (40-byte DIB) that every Windows version since 3.0 reads natively. 32-bit BMPs with alpha and 16-bit BMPs may be inconsistently rendered by very old viewers — choose 24-bit for maximum compatibility with legacy GDI-based applications.

Can I shrink BMP output without dropping resolution?

Two paths. First, lower the Image Bit Depth to 8-bit and pick a smaller Image Color Palette Size (16, 64, 128, or 256 colors) — this can cut size 3-6x on flat or animated content with limited palettes. Second, BMP supports 4-bit and 8-bit RLE compression for indexed images per Microsoft's spec; XConvert's IMAGE_COMPRESSION_BMP option enables this when you select an indexed mode. Photographic frames with smooth gradients gain little from RLE.

Why does my BMP look slightly different from the AVI playback?

Two reasons. (1) AVI codecs that use chroma subsampling (4:2:0 like H.264, MPEG-4 ASP) reconstruct color at decode time; the upsampled RGB written to BMP is mathematically identical to what your video player shows but may differ from the encoder's internal source. (2) If you set a Resolution Percentage below 100%, the resampling filter introduces interpolation that's correct but not pixel-identical to the source. For exact source pixels, keep resolution Original and bit depth at 24-bit.

Is there a file-size or count limit?

XConvert handles AVI inputs up to multi-gigabyte sizes per file in batch. For very long clips with multi-screenshot extraction, BMP output volume balloons quickly — a 30-minute 1080p AVI sampled at one frame per second produces 1,800 BMPs at ~6 MB each (11 GB total). Either narrow the time window before upload, or pick AVI to JPG for routine sharing where lossless isn't required.