linux - ffmpeg : Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height -

i'm experiencing troubles running ffmpeg on synology. i'm trying convert .avi video mp4.

here command :

ffmpeg -i vid20160623.avi -acodec libfaac -b:a 128k -vcodec mpeg4 -b:v 1200k -flags +aic+mv4 -f mp4 vid20160623.mp4

and logs :

ffmpeg version 2.7.1 copyright (c) 2000-2015 ffmpeg developers   built gcc 4.9.3 (crosstool-ng 1.20.0) 20150311 (prerelease)   configuration: --prefix=/usr --incdir='${prefix}/include/ffmpeg' --arch=arm --target-os=linux --cross-prefix=/usr/local/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi- --enable-cross-compile --enable-optimizations --enable-pic --enable-gpl --enable-shared --disable-static --enable-version3 --enable-nonfree --enable-libfaac --enable-encoders --enable-pthreads --disable-bzlib --disable-protocol=rtp --disable-muxer=image2 --disable-muxer=image2pipe --disable-swscale-alpha --disable-ffserver --disable-ffplay --disable-devices --disable-bzlib --disable-altivec --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libmp3lame --disable-vaapi --disable-decoder=amrnb --disable-encoder=zmbv --disable-encoder=dca --disable-encoder=ac3 --disable-encoder=ac3_fixed --disable-encoder=eac3 --disable-decoder=dca --disable-decoder=eac3 --disable-decoder=truehd --cc=/usr/local/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-ccache-gcc   libavutil      54. 27.100 / 54. 27.100   libavcodec     56. 41.100 / 56. 41.100   libavformat    56. 36.100 / 56. 36.100   libavdevice    56.  4.100 / 56.  4.100   libavfilter     5. 16.101 /  5. 16.101   libswscale      3.  1.101 /  3.  1.101   libswresample   1.  2.100 /  1.  2.100   libpostproc    53.  3.100 / 53.  3.100 input #0, avi, 'vid20160623.avi':   metadata:     encoder         : mencoder git-ab94fc6-4.4.3   duration: 00:20:18.07, start: 0.000000, bitrate: 1197 kb/s     stream #0:0: video: mpeg4 (advanced simple profile) (xvid / 0x44495658), yuv420p, 624x352 [sar 1:1 dar 39:22], 1056 kb/s, 25 fps, 23.98 tbr, 25 tbn, 23.98 tbc     stream #0:1: audio: mp3 (u[0][0][0] / 0x0055), 48000 hz, stereo, s16p, 128 kb/s output #0, mp4, vid20160623.mp4':   metadata:     encoder         : mencoder git-ab94fc6-4.4.3     stream #0:0: video: mpeg4, none, q=2-31, 128 kb/s, sar 351:352 dar 0:0, 23.98 fps     metadata:       encoder         : lavc56.41.100 mpeg4     stream #0:1: audio: aac, 0 channels, 128 kb/s     metadata:       encoder         : lavc56.41.100 libfaac stream mapping:   stream #0:0 -> #0:0 (mpeg4 (native) -> mpeg4 (native))   stream #0:1 -> #0:1 (mp3 (native) -> aac (libfaac)) error while opening encoder output stream #0:0 - maybe incorrect parameters such bit_rate, rate, width or height 

i tried reduce b:a , b:v did not work.

any welcome.

looks encoder not recognizing resolution of output stream. also, codec frame rate different actual frame rate. try,

ffmpeg -i vid20160623.avi -acodec libfaac -b:a 128k -vf "scale=624:352,setsar=1" -vcodec mpeg4 -r 25 -b:v 1200k -flags +aic+mv4 -f mp4 vid20160623.mp4