GSM to IRCAM Converter

Encode GSM telephony speech into IRCAM scientific format

Drop files here. 1 GB maximum file size or Sign Up
to
Facebook Amazon Microsoft Tesla Nestle Walmart L'Oreal

Scientific Audio Standard

Convert GSM speech into the IRCAM SDIF format — the standard of the Paris-based acoustics research institute for audio analysis.

Research Pipeline Ready

Bring GSM telephony recordings into IRCAM format for compatibility with scientific sound analysis and acoustic research tools.

Confidential Handling

All GSM uploads are erased after processing. IRCAM outputs are cleaned from servers within 24 hours.

How to convert GSM to IRCAM

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose ircam or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your ircam file right afterwards

About formats

GSM 06.10 (Full Rate) is the foundational speech codec of the Global System for Mobile Communications standard, ratified by ETSI in 1991 and deployed across hundreds of cellular networks worldwide. Operating at a fixed 13 kbit/s, the algorithm applies Regular Pulse Excitation with Long-Term Prediction (RPE-LTP) to compress 20 ms frames of 8 kHz mono speech into just 33 bytes each. This approach models the vocal tract as a linear predictive filter, encodes the excitation signal, and leverages pitch periodicity for further reduction — tuned to deliver intelligible voice under the bandwidth constraints of early digital mobile channels. The codec powers not only GSM telephony but also many VoIP applications, voicemail systems, and IVR platforms that benefit from its low bitrate. Three concrete advantages stand out. First, extraordinary compression: one minute of speech fits in roughly 100 KB, enabling efficient storage and transmission. Second, universal tooling — libraries such as libgsm and SoX handle encoding and decoding on every major platform. Third, a royalty-free patent landscape that has encouraged adoption across open-source telephony projects like Asterisk and FreeSWITCH.
Initial release: 1991
IRCAM sound files originate from the Institut de Recherche et Coordination Acoustique/Musique — one of the world's foremost computer music laboratories, founded by composer Pierre Boulez in Paris. The format was created in the early 1980s to serve the research needs of IRCAM and has since been adopted by academic and artistic communities working at the intersection of science and sound. An IRCAM file begins with a 1024-byte header containing a magic number, sample rate, channel count, and an encoding type field that supports linear PCM (16/32-bit integer and 32-bit float), mu-law, and A-law variants. The header block also accommodates free-form annotation text, allowing researchers to embed experiment metadata directly in the audio file. Because the payload is uncompressed by default, recordings maintain full fidelity through successive analysis and resynthesis cycles — essential in psychoacoustic experimentation. Software such as Csound, libsndfile, and SoX reads and writes the format natively. Key advantages include a well-defined header that eliminates parsing ambiguity, support for floating-point samples essential in scientific DSP work, and deep roots in the computer music community ensuring continued tooling.
Developer: IRCAM
Initial release: 1983

Frequently Asked Questions

What is IRCAM?

IRCAM SDIF is a scientific audio format developed at the Institute for Research and Coordination in Acoustics/Music in Paris.

Why convert GSM to IRCAM?

IRCAM format is used in acoustic research tools and sound analysis software. Converting prepares GSM speech for scientific workflows.

What software reads IRCAM files?

IRCAM-developed analysis tools, SoX, and some scientific audio processing libraries can read and write IRCAM SDIF files.

Is IRCAM a lossless format?

IRCAM can store uncompressed PCM audio. The decoded GSM signal is preserved without additional compression in the IRCAM container.

Is conversion secure?

GSM uploads are deleted immediately. IRCAM results are purged from our servers within 24 hours.