SubRip

SubRip refers to a software tool and to the subtitle file format it produces. The SubRip tool performs optical character recognition on video frames to detect subtitle text and timing information, then outputs a plain text file in the SubRip Text format with the .srt extension.

The program can process a range of input sources, such as digital video files and DVD subtitle streams. It identifies frames where subtitles appear, applies OCR to recognize the characters, and saves the results as a sequence of timed subtitle entries. The resulting .srt file can be edited with a text editor or specialized subtitle tools, and is broadly compatible with many media players. Because OCR is not perfect, the extracted text often requires manual correction and synchronization.

The SubRip Text format consists of blocks separated by blank lines. Each block starts with a sequential index number, followed by a timestamp line formatted as hours:minutes:seconds,milliseconds, then an arrow, and a second timestamp. The subtitle text appears on one or more lines after the timestamp. A final blank line ends the block. The format is a simple, human-readable plain text standard that supports Unicode when encoded appropriately and is widely supported by video players and subtitle editors such as VLC, MPC-HC, Aegisub, and Subtitle Edit.

In practice, SubRip and the .srt format have become a common foundation for subtitle distribution and interoperability across platforms, due to their simplicity and broad compatibility.