Boot.img.lz4 ((better)) Jun 2026

✅ The bootloader decompresses the image into RAM before execution. LZ4’s speed reduces boot time significantly compared to Gzip or LZMA.

At its core, a boot.img.lz4 file is a standard that has been compressed using the LZ4 algorithm .

You will see files like:

lz4 -d boot.img.lz4 boot.img

This happens if the LZ4 frame is malformed or truncated. Try redownloading the factory image. boot.img.lz4

When you download firmware from Sony, Xiaomi, or Google (e.g., the factory images for Pixel 6/7/8), you often get a zip file containing boot.img.lz4 instead of boot.img .

This will output boot.img.lz4 directly in $OUT/ . To generate both a compressed and uncompressed version, use: ✅ The bootloader decompresses the image into RAM

lz4 -9 new-boot.img new-boot.img.lz4

: Using LZ4 for the kernel and ramdisk can reduce total device boot time by 500ms to 1000ms compared to older methods like Gzip. You will see files like: lz4 -d boot