M2V to AMR Converter

M2V is a file format containing MPEG-2 video elementary streams without an encapsulating container or associated audio data. Standardized as part of ISO/IEC 13818-2 (also known as ITU-T H.262) by the Moving Picture Experts Group in 1995, M2V stores raw compressed video exactly as it would appear within an MPEG-2 program or transport stream, but stripped of all multiplexing overhead. This makes M2V files primarily useful in professional authoring workflows, particularly DVD production, where video and audio streams are prepared and encoded separately before being muxed together into the final container format. M2V streams support both interlaced and progressive scan modes at resolutions ranging from standard definition up to 1920x1080 HD, with bit rates typically ranging from 2 to 15 Mbps for consumer content and up to 80 Mbps in professional applications. The use of both intra-coded frames and predictive frames provides an effective balance between compression efficiency and random access capability. Because M2V contains only video with no audio or synchronization information, it requires pairing with a separate audio file for complete playback. DVD authoring software commonly expects M2V input alongside AC3 or LPCM audio files, making this format an essential intermediate step in professional disc mastering and broadcast preparation workflows.

AMR (Adaptive Multi-Rate) is a compressed audio format optimized for speech, standardized by the European Telecommunications Standards Institute and adopted as a mandatory codec for GSM and 3G mobile networks. The codec dynamically switches between eight bit rates — from 4.75 to 12.2 kbps — depending on network conditions and background noise levels. When link quality drops, the encoder shifts to a lower rate, trading marginal clarity for transmission reliability. This adaptive mechanism is defined by the 3GPP specifications and represents one of the most widely deployed voice codecs globally, used in billions of mobile calls. The primary advantage is compression efficiency: one minute of AMR audio at 12.2 kbps occupies roughly 90 KB, practical for voice memos, voicemail, and MMS on bandwidth-constrained networks. Another benefit is built-in voice activity detection and comfort noise generation, reducing transmission during silence. While AMR is unsuitable for music due to its narrow bandwidth (300-3400 Hz), it excels at delivering intelligible speech under challenging network conditions.