Conversion error webm to mp4

[akkidongre-zz]

Hi limistah,

Good work there! Thank you.

I tried to convert a webm file into mp4 using "-vcodec h264 -acodec aac -strict -2 output.mp4". It works in videoconverter.js but whereas doesn't work here.
This is the output I got.

---

FFMPEG is ready

File Received

Received command: -i video-1585897663328.webm -vcodec h264 -acodec aac -strict -2 output.mp4. Processing with 33554432 bits.

ffmpeg version 2.2.1 Copyright (c) 2000-2014 the FFmpeg developers

built on Jun 9 2014 20:24:32 with emcc (Emscripten GCC-like replacement) 1.12.0 (commit 6960d2296299e96d43e694806f5d35799ef8d39c)

configuration: --cc=emcc --prefix=/Users/bgrinstead/Sites/videoconverter.js/build/ffmpeg/../dist --extra-cflags='-I/Users/bgrinstead/Sites/videoconverter.js/build/ffmpeg/../dist/include -v' --enable-cross-compile --target-os=none --arch=x86_32 --cpu=generic --disable-ffplay --disable-ffprobe --disable-ffserver --disable-asm --disable-doc --disable-devices --disable-pthreads --disable-w32threads --disable-network --disable-hwaccels --disable-parsers --disable-bsfs --disable-debug --disable-protocols --disable-indevs --disable-outdevs --enable-protocol=file --enable-libvpx --enable-gpl --extra-libs='/Users/bgrinstead/Sites/videoconverter.js/build/ffmpeg/../dist/lib/libx264.a /Users/bgrinstead/Sites/videoconverter.js/build/ffmpeg/../dist/lib/libvpx.a'

libavutil 52. 66.100 / 52. 66.100

libavcodec 55. 52.102 / 55. 52.102

libavformat 55. 33.100 / 55. 33.100

libavdevice 55. 10.100 / 55. 10.100

libavfilter 4. 2.100 / 4. 2.100

libswscale 2. 5.102 / 2. 5.102

libswresample 0. 18.100 / 0. 18.100

libpostproc 52. 3.100 / 52. 3.100

[h264 @ 0xed8d60] Warning: not compiled with thread support, using thread emulation

Guessed Channel Layout for Input Stream #0.0 : mono

Input #0, matroska,webm, from 'video-1585897663328.webm':

Metadata:

 encoder         : Chrome 

Duration: N/A, start: 0.000000, bitrate: N/A

 Stream #0:0(eng): Audio: opus, 48000 Hz, mono (default) 

 Stream #0:1(eng): Video: h264 (Constrained Baseline), yuv420p, 640x480, SAR 1:1 DAR 4:3, 30.33 fps, 30 tbr, 1k tbn, 60 tbc (default) 

[abuffer @ 0x12327c0] Unable to parse option value "(null)" as sample format

 Last message repeated 1 times
Last message repeated 1 times 

[abuffer @ 0x12327c0] Error setting option sample_fmt to value (null).

[graph 1 input from stream 0:0 @ 0x1232760] Error applying options to the filter.

Error opening filters!

Finished processing (took 2407ms)

Command Completed, check the console

The output file was of size 0 bytes. Please help!
Thank you

[limistah]

Can you share the file that you used?