[FFmpeg-user] Usages about multi outputs

[xiaoyaobms at 163.com]

Hi,

I am not sure if anyone asked this kind of question before. 
Now I want to build a system with one In and N outs with FFMPEG.
The system likes below:
In---->deinterlace--->subtitle---->delogo--->logo
                                                                                |--------- scale 0--->venc_0 + aenc_0--->out 0
                                                                                |----------scale 1--->venc _1 + aenc_1--->out 1
I tried to build the system with below command, but it failed., and I escaped the encoding parameters for simple.

./ffmpeg -i input.mp4 -i logo.png -filter_complex "yadif=deint=1,subtitles=subtitle.ass,delogo=x=60:y=60:w=100:h=77:band=10,overlay=10:10,split=2[a][b]" -map "[a]" -map 0:a -filter_complex scale=640:-1 -pass 1 -vcodec libx264 -r 25 -b:v 230k -profile:v high -c:a libfdk_aac -b:a 64k -ar 44100 -profile:a aac_he output1.mp4 -map "[b]" -map 0:a -filter_complex scale=960:-1 -pass 1 -vcodec libx264 -r 25 -b:v 550k -profile:v high -c:a libfdk_aac -b:a 64k -ar 44100 -profile:a aac_he output2.mp4

There is error outputs like below:
Cannot find a matching stream for unlabeled input pad 0 on filter Parsed_scale_0

Can anyone give me some suggestion for such usage? Thanks a lot!