I need to combine two mp3 files by using ffMpeg.
I use this code, but it doesn't work
I want to execute this
ffmpeg -i input1.mp3 -i input2.mp3 -filter_complex amerge -c:a libmp3lame -q:a 4 output.mp3
Why isn't my code working?
and my complete output log , problem Unknown encoder 'libmp3lame'
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout ffmpeg version n2.4.2 Copyright (c) 2000-2014 the FFmpeg developers
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout built on Oct 7 2014 15:05:17 with gcc 4.8 (GCC)
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout configuration: --target-os=linux --cross-prefix=/home/sb/Source-Code/ffmpeg-android/toolchain-android/bin/arm-linux-androideabi- --arch=arm --cpu=cortex-a8 --enable-runtime-cpudetect --sysroot=/home/sb/Source-Code/ffmpeg-android/toolchain-android/sysroot --enable-pic --enable-libx264 --enable-libass --enable-libfreetype --enable-libfribidi --enable-fontconfig --enable-pthreads --disable-debug --disable-ffserver --enable-version3 --enable-hardcoded-tables --disable-ffplay --disable-ffprobe --enable-gpl --enable-yasm --disable-doc --disable-shared --enable-static --pkg-config=/home/sb/Source-Code/ffmpeg-android/ffmpeg-pkg-config --prefix=/home/sb/Source-Code/ffmpeg-android/build/armeabi-v7a --extra-cflags='-I/home/sb/Source-Code/ffmpeg-android/toolchain-android/include -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fno-strict-overflow -fstack-protector-all' --extra-ldflags='-L/home/sb/Source-Code/ffmpeg-android/toolchain-android/lib -Wl,-z,relro -Wl,-z,now -pie' --extra-libs='-lpng -lexpat -lm' --extra-cxxflags=
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout libavutil 54. 7.100 / 54. 7.100
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout libavcodec 56. 1.100 / 56. 1.100
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout libavformat 56. 4.101 / 56. 4.101
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout libavdevice 56. 0.100 / 56. 0.100
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout libavfilter 5. 1.100 / 5. 1.100
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout libswscale 3. 0.100 / 3. 0.100
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout libswresample 1. 1.100 / 1. 1.100
01-06 11:48:13.560 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout libpostproc 53. 0.100 / 53. 0.100
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Input #0, mp3, from '/storage/emulated/0/a.mp3':
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Metadata:
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout title : Creep
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout album : Pablo Honey
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout track : 2/13
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout disc : 1/1
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout artist : Radiohead
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout genre : Alternative
-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout publisher : EMI Music Distribution
-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout album_artist : Radiohead
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout composer : Colin Greenwood/Ed O'Brien/Jonny Greenwood/Phil Selway/Thom Yorke
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout date : 1993
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Duration: 00:03:55.91, start: 0.025057, bitrate: 320 kb/s
01-06 11:48:13.572 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 320 kb/s
01-06 11:48:13.573 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Metadata:
01-06 11:48:13.573 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout encoder : LAME3.97
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout [mp3 @ 0x2b403a90] Estimating duration from bitrate, this may be inaccurate
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Input #1, mp3, from '/storage/emulated/0/b.mp3':
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Metadata:
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout title : This is Love
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout artist : Chirs de Burgh
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout album : This Way Up
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout date : 1994
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout comment :
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Duration: 00:03:47.67, start: 0.000000, bitrate: 128 kb/s
01-06 11:48:13.577 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Stream #1:0: Audio: mp3, 44100 Hz, stereo, s16p, 128 kb/s
01-06 11:48:13.579 6119-6472/com.uraroji.garage.android.mp3recvoice D/test: shellout Unknown encoder 'libmp3lame'
01-06 11:48:13.580 6119-6473/com.uraroji.garage.android.mp3recvoice D/dalvikvm: threadid=14: exiting
01-06 11:48:13.580 6119-6473/com.uraroji.garage.android.mp3recvoice D/dalvikvm: threadid=14: bye!
01-06 11:48:13.580 6119-6119/com.uraroji.garage.android.mp3recvoice D/test: processComplete 1
01-06 11:48:13.580 6119-6472/com.uraroji.garage.android.mp3recvoice D/dalvikvm: threadid=13: exiting
01-06 11:48:13.581 6119-6472/com.uraroji.garage.android.mp3recvoice D/dalvikvm: threadid=13: bye!
FFmpeg does not have a native MP3 encoder, so you have to use an external library (libmp3lame or libshine) for MP3 encoding support. However, your ffmpeg build was not compiled with --enable-libmp3lame or --enable-libshine. You will have to re-compile ffmpeg.
libmp3lame is more common, but libshine is for fixed-point MP3 encoding which may be faster on your ARM device (but I've never performed any comparisons).
Your command uses the amerge filter to merge two stereo audio files. This will result in a 4-channel output. If you want to downmix the output to stereo then add -ac 2.