Merge pull request #238 from dexterlb/voc_grid_multiple_stream_support

voc_grid: multiple stream support

software/voc_grid/README.md

@@ -8,7 +8,7 @@ Streams are scaled down to thumbnail-like.
 ### Usage
 
 ```bash
-$ ./run.sh (stream|play) stream1 stream2 ...
+$ ./run.sh (stream|play) source1 source2 ...
 ```
 
 The script has two possible modes: stream and play.
@@ -18,6 +18,18 @@ In play mode, the grid is shown on the local machine via mpv.
 
 The script is configured via `config.sh`.
 
+Each source can be a HLS stream, a RTMP stream or whatever ffmpeg understands.
+
+You can also append `@<video stream number>:<audio stream number>` to each source
+to select a specific video/audio stream from it (if it contains multiple)
+
+Here's an example:
+
+```
+$ ./run.sh play 'tcp://voctop24.video.fosdem.org:8899@2:1' 'tcp://voctop25.video.fosdem.org:8899@2:1' 'tcp://voctop26.video.fosdem.org:8899@2:1' 'tcp://voctop27.video.fosdem.org:8899@2:1'
+$ # '@2:1' means to select the second video stream (which is 720p) and the first audio stream
+```
+
 ### TODO
 
 Hardware acceleration is not fully utilised at the moment: all the compositing

software/voc_grid/config.sh

@@ -4,7 +4,7 @@ vid_width=320               # width of each video box
 vid_height=180              # height of each video box
 vol_height=40               # height of vu meter under each video box
 vol_default_num_channels=2  # if video has a different number of channels than specified, it will work fine but will be uglier
-grid_x=4                    # number of horizontal subdivisions
+grid_x=2                    # number of horizontal subdivisions
 grid_y=2                    # number of vertical subdivisions
 # the total number of video boxes is equal to grid_x * grid_y
 

software/voc_grid/run.sh

@@ -15,6 +15,11 @@ function msg {
     echo "${@}" >&2
 }
 
+function die {
+    msg "${@}"
+    exit 1
+}
+
 function make_volume {
     echo "[${1}]showvolume=m=p:w=${vid_width}:h=${vol_height}:dm=1:f=0:c=if(gte(VOLUME\,-0.2)\,0x0000ff\,if(gte(VOLUME\,-2)\,0x00ffff\,0x00ff00))[${2}_uncropped]; "
     echo "[${2}_uncropped] scale=${vid_width}:${volbar_final_height} [${2}]; "
@@ -80,15 +85,54 @@ function stack_streams_into_grid {
     echo "xstack=inputs=${n}:layout=${all_specs}[${out_stream}]"
 }
 
+function get_num_streams_and_filename {
+    local filename="$(echo "${1}" | cut -d '@' -f 1)"
+    local req_video_stream_number="$(echo "${1}" | cut -s -d '@' -f 2 | cut -s -d ':' -f 1)"
+    local req_audio_stream_number="$(echo "${1}" | cut -s -d '@' -f 2 | cut -s -d ':' -f 2)"
+    if [[ -z "${req_video_stream_number}" ]]; then
+        req_video_stream_number=1
+    fi
+    if [[ -z "${req_audio_stream_number}" ]]; then
+        req_audio_stream_number=1
+    fi
+
+    local stream_data="$(ffprobe "${filename}" 2>&1 | grep -P 'Stream #.*(Video|Audio)')"
+    local num_video_streams="$(echo "${stream_data}" | grep -F "Video:" | wc -l)"
+    local num_audio_streams="$(echo "${stream_data}" | grep -F "Audio:" | wc -l)"
+    if [[ ${num_video_streams} -le 1 ]]; then
+        num_video_streams=1
+    fi
+    if [[ ${num_audio_streams} -le 1 ]]; then
+        num_audio_streams=1
+    fi
+    msg "${filename} has ${num_video_streams} video streams and ${num_audio_streams} audio streams"
+    msg "filename: ${filename}; requested video stream: ${req_video_stream_number}; requested audio stream: ${req_audio_stream_number}"
+
+    if ! [[ "${req_video_stream_number}" -ge 1 && "${req_video_stream_number}" -le "${num_video_streams}" ]]; then
+        die "requested video stream number ${req_video_stream_number} but there are ${num_video_streams} video streams"
+    fi
+    if ! [[ "${req_audio_stream_number}" -ge 1 && "${req_audio_stream_number}" -le "${num_audio_streams}" ]]; then
+        die "requested audio stream number ${req_audio_stream_number} but there are ${num_audio_streams} audio streams"
+    fi
+    echo "${num_video_streams} ${num_audio_streams} ${req_video_stream_number} ${req_audio_stream_number} ${filename}"
+}
+
 function do_stream {
-    in_args=()
-    streams=()
-    i=0
+    local in_args=()
+    local streams=()
+    local i_audio=0
+    local i_video=0
     for arg in "${@}"; do
-        streams+=("${i}:v" "${i}:a")
+        read num_video_streams num_audio_streams req_video_stream_number req_audio_stream_number filename < <(get_num_streams_and_filename "${arg}")
+
+        streams+=("$(( i_video + req_video_stream_number - 1)):v" "$(( i_audio + req_audio_stream_number - 1 )):a")
         in_args+=("-i")
-        in_args+=("${arg}")
-        i=$(( i + 1 ))
+        in_args+=("${filename}")
+
+        # take the first stream from each given source
+        # TODO: implement way to select non-first stream
+        i_audio=$(( i_audio + num_audio_streams ))
+        i_video=$(( i_video + num_video_streams ))
     done
 
     filters="$(stack_streams_into_grid vo "${streams[@]}")"
@@ -98,26 +142,36 @@ function do_stream {
     ffmpeg -y -r 24 "${in_args[@]}" \
         -filter_complex "${filters}" \
         -map '[vo]' -r "${restream_fps}" -c:v libx264 -crf 19 \
+        i=$(( i + 1 ))
         -f "${restream_format}" \
         "${restream_target}"
 }
 
 function do_play {
-    in_args=()
-    streams=()
-    i=0
+    local in_args=()
+    local streams=()
+    local i_audio=0
+    local i_video=0
     for arg in "${@}"; do
-        if [[ "${i}" -eq 0 ]]; then
-            in_args+=("${arg}")
+        read num_video_streams num_audio_streams req_video_stream_number req_audio_stream_number filename < <(get_num_streams_and_filename "${arg}")
+
+        if [[ "${i_audio}" -eq 0 ]]; then
+            # first source must be given as argument
+            in_args+=("${filename}")
         else
-            in_args+=("--external-file=${arg}")
+            in_args+=("--external-file=${filename}")
         fi
-        streams+=("vid$(( i + 1 ))" "aid$(( i + 1 ))")
-        i=$(( i + 1 ))
+        streams+=("vid$(( i_video + req_video_stream_number ))" "aid$(( i_audio + req_audio_stream_number ))")
+
+        # take the first stream from each given source
+        # TODO: implement way to select non-first stream
+        i_audio=$(( i_audio + num_audio_streams ))
+        i_video=$(( i_video + num_video_streams ))
     done
 
     filters="$(stack_streams_into_grid vo "${streams[@]}")"
     msg "filters: ${filters}" >&2
+    msg "files: ${in_args[@]}"
 
     mpv "${in_args[@]}" --lavfi-complex="${filters}" --no-resume-playback --pause=no --background=color
 }