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Autres articles (43)
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Le plugin : Podcasts.
14 juillet 2010, parLe problème du podcasting est à nouveau un problème révélateur de la normalisation des transports de données sur Internet.
Deux formats intéressants existent : Celui développé par Apple, très axé sur l’utilisation d’iTunes dont la SPEC est ici ; Le format "Media RSS Module" qui est plus "libre" notamment soutenu par Yahoo et le logiciel Miro ;
Types de fichiers supportés dans les flux
Le format d’Apple n’autorise que les formats suivants dans ses flux : .mp3 audio/mpeg .m4a audio/x-m4a .mp4 (...) -
List of compatible distributions
26 avril 2011, parThe table below is the list of Linux distributions compatible with the automated installation script of MediaSPIP. Distribution nameVersion nameVersion number Debian Squeeze 6.x.x Debian Weezy 7.x.x Debian Jessie 8.x.x Ubuntu The Precise Pangolin 12.04 LTS Ubuntu The Trusty Tahr 14.04
If you want to help us improve this list, you can provide us access to a machine whose distribution is not mentioned above or send the necessary fixes to add (...) -
Emballe médias : à quoi cela sert ?
4 février 2011, parCe plugin vise à gérer des sites de mise en ligne de documents de tous types.
Il crée des "médias", à savoir : un "média" est un article au sens SPIP créé automatiquement lors du téléversement d’un document qu’il soit audio, vidéo, image ou textuel ; un seul document ne peut être lié à un article dit "média" ;
Sur d’autres sites (7333)
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ffmpeg encoding leaves me with blank space at the end where the video pauses and there is nothing ahead
6 novembre 2022, par Nisarg DesaiI was trying to slice some of the video being played and clip it in mpv.net using a .lua script which uses ffmpeg to encode the webm output. ffmpeg sometimes leaves some seconds blank and without any video/audio ahead while clipping from source. Is there any solution to this ?


The code for the script is given below (was taken from here https://github.com/occivink/mpv-scripts) :


local utils = require "mp.utils"
local msg = require "mp.msg"
local options = require "mp.options"

local ON_WINDOWS = (package.config:sub(1,1) ~= "/")

local start_timestamp = nil
local profile_start = ""

-- implementation detail of the osd message
local timer = nil
local timer_duration = 2

-- folder creation if it doesnt exist
function exists(file)
 local ok, err, code = os.rename(file, file)
 if not ok then
 if code == 13 then
 return true
 end
 end
 return ok, err
end

--- Check if a directory exists in this path
function create_dir(path)
 local dir = "\"" .. path .. "\""
 if not exists(path .."/") then
 os.execute("mkdir " .. dir)
 end
end

function append_table(lhs, rhs)
 for i = 1,#rhs do
 lhs[#lhs+1] = rhs[i]
 end
 return lhs
end

function file_exists(name)
 local f = io.open(name, "r")
 if f ~= nil then
 io.close(f)
 return true
 else
 return false
 end
end

function get_extension(path)
 local candidate = string.match(path, "%.([^.]+)$")
 if candidate then
 for _, ext in ipairs({ "mkv", "webm", "mp4", "avi" }) do
 if candidate == ext then
 return candidate
 end
 end
 end
 return "mkv"
end

function get_output_string(dir, format, input, extension, title, from, to, profile)
 local res = utils.readdir(dir)
 if not res then
 return nil
 end
 local files = {}
 for _, f in ipairs(res) do
 files[f] = true
 end
 local output = format
 output = string.gsub(output, "$f", function() return input end)
 output = string.gsub(output, "$t", function() return title end)
 output = string.gsub(output, "$s", function() return seconds_to_time_string(from, true) end)
 output = string.gsub(output, "$e", function() return seconds_to_time_string(to, true) end)
 output = string.gsub(output, "$d", function() return seconds_to_time_string(to-from, true) end)
 output = string.gsub(output, "$x", function() return extension end)
 output = string.gsub(output, "$p", function() return profile end)
 if ON_WINDOWS then
 output = string.gsub(output, "[/\\|<>?:\"*]", "_")
 end
 if not string.find(output, "$n") then
 return files[output] and nil or output
 end
 local i = 1
 while true do
 local potential_name = string.gsub(output, "$n", tostring(i))
 if not files[potential_name] then
 return potential_name
 end
 i = i + 1
 end
end

function get_video_filters()
 local filters = {}
 for _, vf in ipairs(mp.get_property_native("vf")) do
 local name = vf["name"]
 name = string.gsub(name, '^lavfi%-', '')
 local filter
 if name == "crop" then
 local p = vf["params"]
 filter = string.format("crop=%d:%d:%d:%d", p.w, p.h, p.x, p.y)
 elseif name == "mirror" then
 filter = "hflip"
 elseif name == "flip" then
 filter = "vflip"
 elseif name == "rotate" then
 local rotation = vf["params"]["angle"]
 -- rotate is NOT the filter we want here
 if rotation == "90" then
 filter = "transpose=clock"
 elseif rotation == "180" then
 filter = "transpose=clock,transpose=clock"
 elseif rotation == "270" then
 filter = "transpose=cclock"
 end
 end
 filters[#filters + 1] = filter
 end
 return filters
end

function get_input_info(default_path, only_active)
 local accepted = {
 video = true,
 audio = not mp.get_property_bool("mute"),
 sub = mp.get_property_bool("sub-visibility")
 }
 local ret = {}
 for _, track in ipairs(mp.get_property_native("track-list")) do
 local track_path = track["external-filename"] or default_path
 if not only_active or (track["selected"] and accepted[track["type"]]) then
 local tracks = ret[track_path]
 if not tracks then
 ret[track_path] = { track["ff-index"] }
 else
 tracks[#tracks + 1] = track["ff-index"]
 end
 end
 end
 return ret
end

function seconds_to_time_string(seconds, full)
 local ret = string.format("%02d:%02d.%03d"
 , math.floor(seconds / 60) % 60
 , math.floor(seconds) % 60
 , seconds * 1000 % 1000
 )
 if full or seconds > 3600 then
 ret = string.format("%d:%s", math.floor(seconds / 3600), ret)
 end
 return ret
end

function start_encoding(from, to, settings)
 local args = {
 settings.ffmpeg_command,
 "-loglevel", "panic", "-hide_banner",
 }
 local append_args = function(table) args = append_table(args, table) end

 local path = mp.get_property("path")
 local is_stream = not file_exists(path)
 if is_stream then
 path = mp.get_property("stream-path")
 end

 local track_args = {}
 local start = seconds_to_time_string(from, false)
 local input_index = 0
 for input_path, tracks in pairs(get_input_info(path, settings.only_active_tracks)) do
 append_args({
 "-ss", start,
 "-i", input_path,
 })
 if settings.only_active_tracks then
 for _, track_index in ipairs(tracks) do
 track_args = append_table(track_args, { "-map", string.format("%d:%d", input_index, track_index)})
 end
 else
 track_args = append_table(track_args, { "-map", tostring(input_index)})
 end
 input_index = input_index + 1
 end

 append_args({"-to", tostring(to-from)})
 append_args(track_args)

 -- apply some of the video filters currently in the chain
 local filters = {}
 if settings.preserve_filters then
 filters = get_video_filters()
 end
 if settings.append_filter ~= "" then
 filters[#filters + 1] = settings.append_filter
 end
 if #filters > 0 then
 append_args({ "-filter:v", table.concat(filters, ",") })
 end

 -- split the user-passed settings on whitespace
 for token in string.gmatch(settings.codec, "[^%s]+") do
 args[#args + 1] = token
 end

 -- path of the output
 local output_directory = mp.get_property("options/screenshot-directory")
 -- local checkbool = exists(output_directory.."/")
 -- mp.osd_message("" .. type(checkbool), timer_duration)
 -- if not checkbool then 
 -- os.execute("mkdir" .. output_directory)
 -- end
 if output_directory == "" then
 if is_stream then
 output_directory = "."
 else
 output_directory, _ = utils.split_path(path)
 end
 else
 output_directory = string.gsub(output_directory, "^~", os.getenv("HOME") or "~")
 end
 local input_name = mp.get_property("filename/no-ext") or "encode"
 local title = mp.get_property("media-title")
 local extension = get_extension(path)
 local output_name = get_output_string(output_directory, settings.output_format, input_name, extension, title, from, to, settings.profile)
 if not output_name then
 mp.osd_message("Invalid path " .. output_directory)
 return
 end
 args[#args + 1] = utils.join_path(output_directory, output_name)

 if settings.print then
 local o = ""
 -- fuck this is ugly
 for i = 1, #args do
 local fmt = ""
 if i == 1 then
 fmt = "%s%s"
 elseif i >= 2 and i <= 4 then
 fmt = "%s"
 elseif args[i-1] == "-i" or i == #args or args[i-1] == "-filter:v" then
 fmt = "%s '%s'"
 else
 fmt = "%s %s"
 end
 o = string.format(fmt, o, args[i])
 end
 print(o)
 end
 if settings.detached then
 utils.subprocess_detached({ args = args })
 else
 local res = utils.subprocess({ args = args, max_size = 0, cancellable = false })
 if res.status == 0 then
 mp.osd_message("Finished encoding succesfully")
 else
 mp.osd_message("Failed to encode, check the log")
 end
 end
end

function clear_timestamp()
 timer:kill()
 start_timestamp = nil
 profile_start = ""
 mp.remove_key_binding("encode-ESC")
 mp.remove_key_binding("encode-ENTER")
 mp.osd_message("", 0)
end

function set_timestamp(profile)
 if not mp.get_property("path") then
 mp.osd_message("No file currently playing")
 return
 end
 if not mp.get_property_bool("seekable") then
 mp.osd_message("Cannot encode non-seekable media")
 return
 end
 create_dir(mp.get_property("options/screenshot-directory"))
 if not start_timestamp or profile ~= profile_start then
 profile_start = profile
 start_timestamp = mp.get_property_number("time-pos")
 local msg = function()
 mp.osd_message(
 string.format("encode [%s]: waiting for end timestamp", profile or "default"),
 timer_duration
 )
 end
 msg()
 timer = mp.add_periodic_timer(timer_duration, msg)
 mp.add_forced_key_binding("ESC", "encode-ESC", clear_timestamp)
 mp.add_forced_key_binding("ENTER", "encode-ENTER", function() set_timestamp(profile) end)
 else
 local from = start_timestamp
 local to = mp.get_property_number("time-pos")
 if to <= from then
 mp.osd_message("Second timestamp cannot be before the first", timer_duration)
 timer:kill()
 timer:resume()
 return
 end
 clear_timestamp()
 mp.osd_message(string.format("Encoding from %s to %s"
 , seconds_to_time_string(from, false)
 , seconds_to_time_string(to, false)
 ), timer_duration)
 -- include the current frame into the extract
 local fps = mp.get_property_number("container-fps") or 30
 to = to + 1 / fps / 2
 local settings = {
 detached = false,
 container = "",
 only_active_tracks = false,
 preserve_filters = true,
 append_filter = "",
 codec = "-c:v libvpx-vp9 -lossless 1 -b:v 1000k -deadline good",
 output_format = "$f_$n.webm",
 output_directory = "",
 ffmpeg_command = "ffmpeg",
 print = true,
 }
 if profile then
 options.read_options(settings, profile)
 if settings.container ~= "" then
 msg.warn("The 'container' setting is deprecated, use 'output_format' now")
 settings.output_format = settings.output_format .. "." .. settings.container
 end
 settings.profile = profile
 else
 settings.profile = "default"
 end 
 start_encoding(from, to, settings)
 end
end

mp.add_key_binding(nil, "set-timestamp", set_timestamp)



-
Revision dbea726daf : Adds a source variance computation function Adds a function to compute source v
1er août 2013, par Deb MukherjeeChanged Paths :
Modify /vp9/common/vp9_common_data.c
Modify /vp9/common/vp9_common_data.h
Modify /vp9/encoder/vp9_encodeframe.c
Adds a source variance computation functionAdds a function to compute source variance for various
sb_types to be used for pruning mode and partition searches.
[The existing activity measure function is currently specialized
for only 16x16 MBs and needs to be updated].Change-Id : I22a41e6f1430184201487326fdbebb9b47e6fc24
-
Problem with ffplay from webcam stream using complex filters
29 mai 2022, par efelbarI'm trying to stream video from a webcam (at
/dev/video2
) through ffplay to scale and recolor it, add some text, and then reduce the number of colors with palettes. I don't get any errors, but running the ffplay command :

ffplay -i /dev/video2 -vf "hflip,\
 colorbalance=\
 rs=0.4:\
 bs=-0.4\
 ,\
 scale=\
 trunc(iw/8):\
 trunc(ih/8)\
 ,\
 drawtext=\
 text=\
 'efelbar':\
 fontcolor=white:\
 fontsize=10:\
 box=1:\
 boxcolor=black:\
 boxborderw=5:\
 x=(w-text_w)/2:\
 y=(h-text_h)/2\
 ,\
 split[s0][s1];\
 [s0]palettegen=\
 max_colors=16\
 [p];\
 [s1][p]paletteuse"



seems to stall, and fails to produce video output.


Running the simpler command
ffplay -i /dev/video2 -vf "split[s0][s1];[s0]palettegen=max_colors=16[p];[s1][p]paletteuse"
, which takes a stream from a webcam and (should) reduce the number of colors, results in it just sitting there without showing the actual output stream. This might just be a performance issue because I'm on older hardware, but it doesn't give output relfective of that.

The output of that command is as follows :


ffplay version n5.0 Copyright (c) 2003-2022 the FFmpeg developers
 built with gcc 11.2.0 (GCC)
 configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-amf --enable-avisynth --enable-cuda-llvm --enable-lto --enable-fontconfig --enable-gmp --enable-gnutls --enable-gpl --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libdav1d --enable-libdrm --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libiec61883 --enable-libjack --enable-libmfx --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librav1e --enable-librsvg --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libsvtav1 --enable-libtheora --enable-libv4l2 --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxcb --enable-libxml2 --enable-libxvid --enable-libzimg --enable-nvdec --enable-nvenc --enable-shared --enable-version3
 libavutil 57. 17.100 / 57. 17.100
 libavcodec 59. 18.100 / 59. 18.100
 libavformat 59. 16.100 / 59. 16.100
 libavdevice 59. 4.100 / 59. 4.100
 libavfilter 8. 24.100 / 8. 24.100
 libswscale 6. 4.100 / 6. 4.100
 libswresample 4. 3.100 / 4. 3.100
 libpostproc 56. 3.100 / 56. 3.100
Input #0, video4linux2,v4l2, from '/dev/video2':B sq= 0B f=0/0 
 Duration: N/A, start: 254970.739108, bitrate: 147456 kb/s
 Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 640x480, 147456 kb/s, 30 fps, 30 tbr, 1000k tbn



I'm running this on a thinkpad t420s, so I definitely wouldn't be surprised if my laptop just can't process video that quickly. If that is the case, suggestions for optimizations would be great !