Convert Flash Video (.f4v) to Adaptive Multi-Rate Audio (.amr) online for free. Fast, secure video conversion with no watermarks or registration.
Conversion settings — add a file to adjust
Upload your .f4v file by dragging it into the upload area or clicking to browse.
Choose your output settings. The default settings work great for most files.
Click Convert and download your .amr file when it's ready.
F4V is Adobe's MPEG-4 Flash video container pairing H.264 video with AAC audio. AMR (Adaptive Multi-Rate) is a narrowband speech codec standardized by 3GPP, designed specifically for efficient voice encoding over cellular networks at bitrates from 4.75 to 12.2 kbps. Converting F4V to AMR extracts the audio from a Flash video and compresses it into an ultra-compact voice-optimized format used by mobile carriers and voice messaging systems worldwide.
AMR conversion makes sense when you need to extract speech content from F4V files for use in voice-centric mobile applications. AMR's extreme compression ratio (a one-minute voice clip takes about 100 KB) makes it ideal for voice messages, voicemail systems, and speech storage on devices with very limited memory. It is natively supported by the GSM cellular infrastructure and most mobile operating systems for voice recording and playback.
FFmpeg extracts and decodes the AAC audio from the F4V container, downmixes to mono, resamples to 8 kHz (AMR-NB's fixed sample rate), and encodes using the libopencore-amrnb encoder. The AMR-NB codec operates at one of eight discrete bitrates from 4.75 to 12.2 kbps, with 12.2 kbps providing the best voice clarity. The encoder applies algebraic code-excited linear prediction (ACELP) optimized for human speech frequencies between 300-3400 Hz.
AMR is optimized exclusively for speech — music, sound effects, and ambient audio will sound distorted and metallic. At 12.2 kbps (the highest rate), voice clarity is acceptable for phone call quality. Lower rates introduce noticeable artifacts. The 8 kHz sample rate means frequencies above 4 kHz are completely removed. This format sacrifices audio quality for extreme compression.
| Device | F4V | AMR |
|---|---|---|
| Windows PC | Partial | Partial |
| macOS | Partial | Partial |
| iPhone/iPad | Partial | Partial |
| Android | Partial | Partial |
| Linux | Partial | Partial |
| Web Browser | No |
Resolution: 1920x1080
Bitrate: 8-12 Mbps
H.264 recommended for fast processing
Resolution: 1080x1080
Bitrate: 3.5 Mbps
Square or 9:16 for Reels
Resolution: 1080x1920
Bitrate: 4 Mbps
9:16 vertical, under 60s ideal
Resolution: 1280x720
Bitrate: 5 Mbps
Under 140s, 512MB max
Resolution: 960x540
Bitrate: 2 Mbps
16MB limit for standard, 64MB for document
Resolution: 1280x720
Bitrate: 4 Mbps
F4V to AMR conversion serves a narrow but important use case: extracting speech content from obsolete Flash video for ultra-compact mobile voice applications. It is not suitable for music or general audio content.
Безпечна передача
Завантаження зашифровані через HTTPS
Конфіденційність передусім
Файли автоматично видаляються після обробки
Без реєстрації
Почніть конвертацію миттєво
Працює всюди
| No |
8MB free, 50MB Nitro
Будь-який браузер, будь-який пристрій
| Характеристика | F4V | AMR |
|---|---|---|
| Повна назва | Flash MP4 Video | Adaptive Multi-Rate Audio |
| Розширення | .f4v | .amr |
| Найкраще для | MPEG-4 based | Speech optimized |