Capturing rtmp to m4a on OSX

After trying several ways to achieve the mission: libav, rtmpdump, etc. I finally landed on a method that utilizes vlc. Bravo vlc!!!

1. Install VLC

http://www.videolan.org/vlc/

2. Run following command:

/Applications/VLC.app/Contents/MacOS/VLC -I dummy rtmp://ebsandroid.ebs.co.kr/fmradiofamilypc/familypc1m vlc://quit --no-sout-video --sout-audio --no-sout-rtp-sap --no-sout-standard-sap --ttl=1 --sout-keep --sout "#transcode{acodec=s16l,channels=2}:std{access=file,mux=wav,dst=1.wav}" 2> /dev/null

3. Convert resulting wav file to m4a file:

/usr/bin/afconvert -f mp4f -d aac -q 127 1.wav 1.m4a

Why not let vlc directly save output in mp3 format?

Because, the sound quality is not quite good. It left me with no choice but to record using wav format and then convert it to aac format.

#!/bin/bash

ABSPATH_SELF=$(cd $(dirname $0); pwd -P)

if [ $# -ne 2 ];

then

    echo "Usage: $0 filename duration(unit:min)"

    exit 1

fi

FILENAMEROOT=$1

DURATION=$(($2 * 60))

DATE=$(date +"%Y-%m-%d")

WEEKDAY=$(date +"%A")

if [ "${WEEKDAY}" == "Monday" -o "${WEEKDAY}" == "Tuesday" -o "${WEEKDAY}" == "Wednesday" ];

then

    LEVEL="초급"

else

    LEVEL="중급"

fi

FILENAME1="${ABSPATH_SELF}/${FILENAMEROOT}-${DATE}.m4a"

FILENAME2="${ABSPATH_SELF}/${FILENAMEROOT}-${DATE}(${WEEKDAY}-${LEVEL}).m4a"

FILENAME3="${ABSPATH_SELF}/${FILENAMEROOT}-${DATE}(${WEEKDAY_KOR}).m4a"

EBS_RADIO_URL="rtmp://ebsandroid.ebs.co.kr/fmradiofamilypc/familypc1m"

TMP_WAVFILE="${FILENAME1}.wav"

/Applications/VLC.app/Contents/MacOS/VLC -I dummy ${EBS_RADIO_URL} vlc://quit --no-sout-video --sout-audio --no-sout-rtp-sap --no-sout-standard-sap --ttl=1 --sout-keep --sout "#transcode{acodec=s16l,channels=2}:std{access=file,mux=wav,dst=${TMP_WAVFILE}}" 2> /dev/null &

VLC_PID=$!

sleep ${DURATION}

kill -TERM ${VLC_PID}

sleep 10

/usr/bin/afconvert -f mp4f -d aac -q 127 ${TMP_WAVFILE} ${FILENAME1}

if [ "${FILENAMEROOT}" == "Chinese" -o "${FILENAMEROOT}" == "Japanese" ];

then

    mv ${FILENAME1} ${FILENAME2}

else

    mv ${FILENAME1} ${FILENAME3}

fi

rm -f ${TMP_WAVFILE}

EBS streaming rtmp address list

rtmp://ebsandroid.nefficient.com/groundwavefamilypc/familypc1m"; // 지상파HD

rtmp://ebsandroid.nefficient.com/ebsufamilypc/familypc1m"; //EBSu HD

rtmp://ebsandroid.nefficient.com/fmradiofamilypc/familypc1m"; //FM 라디오 SD

rtmp://ebsandroid.nefficient.com/plus1familypc/familypc1m"; //Plus1 SD

rtmp://ebsandroid.nefficient.com/plus2familypc/familypc1m"; //Plus2 SD

rtmp://ebsandroid.nefficient.com/plus3familypc/familypc1m"; //Plus3 SD