Encode recordings at a speech-oriented bitrate to shrink files - #4
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MediaRecorder was configured for 44.1 kHz at 128 kbps, which is music fidelity applied to a spoken-word journal. That works out to 16 KB/s, so a 50-minute entry produced a ~46 MB file — slow to upload to Drive and needlessly large on device. Switch to mono, 22.05 kHz, 32 kbps AAC, which stays clearly intelligible for voice while cutting file size 4x (~11 MB for the same 50 minutes). Channel count is now set explicitly rather than relying on the platform default. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01WF5hfLpRQLQXoregs2cChs
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Why
A 50-minute journal entry was producing a ~46 MB file. The recorder had been configured for 44.1 kHz at 128 kbps since the initial commit — music fidelity applied to a spoken-word journal:
That's roughly 4x more bitrate than voice needs, and it makes Drive uploads correspondingly slow.
What changed
MediaRecorderAudioRecordernow encodes mono / 22.05 kHz / 32 kbps AAC instead of 44.1 kHz / 128 kbps. Channel count is set explicitly rather than relying on the platform default (which was already mono, but was undocumented).Speech stays clearly intelligible at this rate and remains fine for transcription. Output is still AAC in an
.m4acontainer, so nothing downstream changes — existing recordings play back exactly as before.README updated to state the encoding settings and the resulting file size.
Testing
Not verified by a build:
./gradlew :app:testDebugUnitTestfails at configuration time in this environment because the Android Gradle plugin (com.android.application:9.2.1) cannot be resolved from the available repositories. That failure is independent of this change — it happens before any source is compiled. The diff is threeMediaRecordersetter calls on APIs available since API 7, so worth a quick manual recording check after merge to confirm the audio quality is acceptable to you.Generated by Claude Code