android - What the "No opaque field provided" mean in ffmpeg? -

i use code covert image , wav mp4:

ffmpeg -loop 1 -i img.jpg -i audio.wav -c:v libx264 -c:a aac -strict experimental -b:a 192k -shortest out.mp4 

but got errors:

 05-09 17:00:23.473 26907-27514/com.tian.example e/xx: ffmpeg version 0.11.1 copyright (c) 2000-2012 ffmpeg developers 05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   built on may  9 2016 16:36:21 gcc 4.9 20150123 (prerelease) 05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   configuration: --arch=arm --cpu=cortex-a8 --target-os=linux --enable-runtime-cpudetect --prefix=/data/data/info.guardianproject.ffmpeg/app_opt --enable-pic --disable-shared --enable-static --cross-prefix=/users/tian/documents/adt/android-ndk-r9c/toolchains/arm-linux-androideabi-4.9/prebuilt/darwin-x86_64/bin/arm-linux-androideabi- --sysroot=/users/tian/documents/adt/android-ndk-r9c/platforms/android-16/arch-arm --extra-cflags='-i../x264 -mfloat-abi=softfp -mfpu=neon -fpie -pie' --extra-ldflags='-l../x264 -fpie -pie' --enable-version3 --enable-gpl --disable-doc --enable-yasm --disable-decoders --enable-decoder=mjpeg --enable-decoder=aac --enable-decoder=h264 --disable-encoders --enable-encoder=libx264 --enable-encoder=aac --enable-encoder=h264 --enable-muxers --disable-demuxers --enable-demuxer=image2 --enable-demuxer=wav --disable-parsers --disable-protocols --enable-protocol=file --disable-filters --disable-avresample --disable-libfreetype --disable-indevs --disable-indev=lavfi --disable-outdevs --enable-  libavutil      51. 54.100 / 51. 54.100 05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   libavcodec     54. 23.100 / 54. 23.100 05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   libavformat    54.  6.100 / 54.  6.100 05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   libavdevice    54.  0.100 / 54.  0.100 05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   libavfilter     2. 77.100 /  2. 77.100 05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   libswscale      2.  1.100 /  2.  1.100  05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   libswresample   0. 15.100 /  0. 15.100 05-09 17:00:23.473 26907-27514/com.tian.example e/xx:   libpostproc    52.  0.100 / 52.  0.100 05-09 17:00:23.553 26907-27514/com.tian.example e/xx: [image2 @ 0xb6042100] max_analyze_duration 5000000 reached @ 5000000 05-09 17:00:23.553 26907-27514/com.tian.example e/xx: input #0, image2, '/storage/emulated/0/android/data/com.tian.example/files/tian/frame.jpg': 05-09 17:00:23.553 26907-27514/com.tian.example e/xx:   duration: 00:00:00.04, start: 0.000000, bitrate: n/a 05-09 17:00:23.553 26907-27514/com.tian.example e/xx:     stream #0:0: video: mjpeg, yuvj420p, 320x240 [sar 72:72 dar 4:3], 25 fps, 25 tbr, 25 tbn, 25 tbc 05-09 17:00:23.573 26907-27514/com.tian.example e/xx: guessed channel layout  input stream #1.0 : mono 05-09 17:00:23.573 26907-27514/com.tian.example e/xx: input #1, wav, '/storage/emulated/0/android/data/com.tian.example/files/tian/example/回声_2016_05_07_22_23_20.wav':  05-09 17:00:23.573 26907-27514/com.tian.example e/xx:   duration: 00:00:02.65, bitrate: 705 kb/s 05-09 17:00:23.573 26907-27514/com.tian.example e/xx:     stream #1:0: audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 hz, mono, 705 kb/s 05-09 17:00:23.593 26907-27514/com.tian.example e/xx: [buffer @ 0xb6052070] w:320 h:240 pixfmt:yuvj420p tb:1/25 sar:72/72 sws_param:flags=2 05-09 17:00:23.593 26907-27514/com.tian.example e/xx: [buffersink @ 0xb60520a0] no opaque field provided  05-09 17:00:23.593 26907-27514/com.tian.example e/xx: [abuffer @ 0xb6052100] invalid sample format (null). 05-09 17:00:23.593 26907-27514/com.tian.example e/xx: error opening filters! 

i new ffmpeg.

my mistake. add decoder pcm_s16le, work nice!