VOB to AC3 Converter

VOB (Video Object) is the primary container format used on DVD-Video discs, defined as part of the DVD specification developed by the DVD Forum. The format first appeared with the DVD standard finalized in September 1996 and has since been used on billions of DVD discs produced worldwide. VOB files are based on the MPEG-2 program stream format, containing multiplexed MPEG-2 video alongside audio in AC-3 (Dolby Digital), DTS, MPEG-1 Layer II, or LPCM formats. Beyond audio and video, VOB files also carry DVD subtitle streams as bitmap overlays, navigation data for menu interaction, and chapter point information. The files reside in the VIDEO_TS directory on a DVD disc, with naming conventions (VTS_01_1.VOB, etc.) reflecting the title and part structure of the content. Individual VOB files are limited to approximately 1 GB to accommodate the UDF file system requirements, with longer content spanning multiple files seamlessly. The format supports both NTSC (720x480) and PAL (720x576) video resolutions at bit rates up to 9.8 Mbps for combined audio and video. Integration of video, multi-track audio, subtitles, and navigation into a single program stream made VOB a complete solution for consumer movie delivery. While streaming and newer disc formats have supplanted DVD for new content, VOB remains hugely relevant for accessing the vast library of existing DVD content.

AC3 is the file format associated with Dolby Digital, a perceptual audio coding technology from Dolby Laboratories. This lossy format encodes up to 5.1 channels of surround sound (left, center, right, left surround, right surround, and LFE) into a bitstream typically ranging from 192 to 640 kbps. The algorithm applies a modified discrete cosine transform with psychoacoustic analysis to discard audio information below the threshold of human perception, producing compact files without obvious quality loss. AC3 became the mandatory audio standard for DVD-Video and is widely used in Blu-ray discs, digital television broadcasts (ATSC), and streaming delivery. A primary advantage is multichannel surround capability, bringing cinematic spatial audio into home theater systems. The format also maintains excellent dialogue clarity through its dedicated center channel, ideal for film and television content. Widespread hardware decoder support in receivers, TVs, and set-top boxes means AC3 audio plays back reliably across an enormous installed base of consumer electronics.