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Use, discuss, criticize
13 avril 2011, parTalk to people directly involved in MediaSPIP’s development, or to people around you who could use MediaSPIP to share, enhance or develop their creative projects.
The bigger the community, the more MediaSPIP’s potential will be explored and the faster the software will evolve.
A discussion list is available for all exchanges between users. -
MediaSPIP Player : problèmes potentiels
22 février 2011, parLe lecteur ne fonctionne pas sur Internet Explorer
Sur Internet Explorer (8 et 7 au moins), le plugin utilise le lecteur Flash flowplayer pour lire vidéos et son. Si le lecteur ne semble pas fonctionner, cela peut venir de la configuration du mod_deflate d’Apache.
Si dans la configuration de ce module Apache vous avez une ligne qui ressemble à la suivante, essayez de la supprimer ou de la commenter pour voir si le lecteur fonctionne correctement : /** * GeSHi (C) 2004 - 2007 Nigel McNie, (...) -
MediaSPIP Player : les contrôles
26 mai 2010, parLes contrôles à la souris du lecteur
En plus des actions au click sur les boutons visibles de l’interface du lecteur, il est également possible d’effectuer d’autres actions grâce à la souris : Click : en cliquant sur la vidéo ou sur le logo du son, celui ci se mettra en lecture ou en pause en fonction de son état actuel ; Molette (roulement) : en plaçant la souris sur l’espace utilisé par le média (hover), la molette de la souris n’exerce plus l’effet habituel de scroll de la page, mais diminue ou (...)
Sur d’autres sites (3544)
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Privacy in Business : What Is It and Why Is It Important ?
13 juillet 2022, par Erin — Privacy -
Approaches To Modifying Game Resource Files
16 août 2016, par Multimedia Mike — Game HackingI have been assisting The Translator in the translation of another mid-1990s adventure game. This one isn’t quite as multimedia-heavy as the last title, and the challenges are a bit different. I wanted to compose this post in order to describe my thought process and mental model in approaching this problem. Hopefully, this will help some others understand my approach since what I’m doing here often appears as magic to some of my correspondents.
High Level Model
At the highest level, it is valuable to understand the code and the data at play. The code is the game’s engine and the data refers to the collection of resources that comprise the game’s graphics, sound, text, and other assets.
Simplistic high-level game engine model
Ideally, we want to change the data in such a way that the original game engine adopts it as its own because it has the same format as the original data. It is very undesirable to have to modify the binary engine executable in any way.
Modifying The Game Data Directly
How to modify the data ? If we modify the text strings for the sake of language translation, one approach might be to search for strings within the game data files and change them directly. This model assumes that the text strings are stored in a plain, uncompressed format. Some games might store these strings in a text format which can be easily edited with any text editor. Other games will store them as binary data.
In the latter situation, a game hacker can scan through data files with utilities like Unix ‘strings’ to find the resources with the desired strings. Then, use a hex editor to edit the strings directly. For example, change “Original String”…
0098F800 00 00 00 00 00 00 00 4F 72 69 67 69 6E 61 6C 20 .......Original 0098F810 53 74 72 69 6E 67 00 00 00 00 00 00 00 00 00 00 String..........
…to “Short String” and pad the difference in string lengths using spaces (0x20) :
0098F800 00 00 00 00 00 00 00 53 68 6F 72 74 20 53 74 72 .......Short Str 0098F810 69 6E 67 20 20 20 00 00 00 00 00 00 00 00 00 00 ing ..........
This has some obvious problems. First, translated strings need to be of equal our smaller length compared to the original. What if we want to encode “Much Longer String” ?
0098F800 00 00 00 00 00 00 00 4D 75 63 68 20 4C 6F 6E 67 .......Much Long 0098F810 65 72 20 53 74 72 00 00 00 00 00 00 00 00 00 00 er Str..........
It won’t fit. The second problem pertains to character set limitations. If the font in use was only designed for ASCII, it’s going to be inadequate for expressing nearly any other language.
So a better approach is needed.
Understanding The Data Structures
An alternative to the approach outlined above is to understand the game’s resources so they can be modified at a deeper level. Here’s a model to motivate this investigation :
Model of the game resource archive format
This is a very common layout for such formats : there is a file header, a sequence of resource blocks, and a trailing index which describes the locations and types of the foregoing blocks.
What use is understanding the data structures ? In doing so, it becomes possible to write new utilities that disassemble the data into individual pieces, modify the necessary pieces, and then reassemble them into a form that the original game engine likes.
It’s important to take a careful, experimental approach to this since mistakes can be ruthlessly difficult to debug (unless you relish the thought of debugging the control flow through an opaque DOS executable). Thus, the very first goal in all of this is to create a program that can disassemble and reassemble the resource, thus creating an identical resource file. This diagram illustrates this complex initial process :
Rewriting the game resource file
So, yeah, this is one of the most complicated “copy file” operations that I can possibly code. But it forms an important basis, since the next step is to carefully replace one piece at a time.
Modifying a specific game resource
This diagram shows a simplistic model of a resource block that contains a series of message strings. The header contains pointers to each of the strings within the block. Instead of copying this particular resource block directly to the new file, a proposed modification utility will intercept it and rewrite the entire thing, writing new strings of arbitrary length and creating an adjusted header which will correctly point to the start of each new string. Thus, translated strings can be longer than the original strings.
Further Work
Exploiting this same approach, we can intercept and modify other game resources including fonts, images, and anything else that might need to be translated. I will explore specific examples in a later blog post.Followup
- Translating Return to Ringworld, in which I apply the ideas expressed in this post.
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compiling ffmpeg for Mac OSX High Sierra 10.13
29 juillet 2021, par MartinHello I made an electron app that uses ffmpeg to combine audio and renders video, it works fine on windows, linux, and modern mac osx computers, but a user has reported to me that on an older version of mac osx such as High Sierra 10.13, the way that I have setup ffmpeg does not work.


I have a virtual machine with High Sierra v10.13 where I install
RenderTune-mac.dmg
from my RenderTune releases page, then I download 2 audio files and the image from this link. I open RenderTune, and try render a video. My command to combine the audio files into a single mp3 works fine, but when I try to combine that mp3 with the image file, the ffmpeg build I have packaged with my electron app fails with this error :

Command was killed with SIGABRT (Aborted): /Applications/RenderTune.app/Contents/Resources/ffmpeg -loop 1 -framerate 2 -i /Users/martin/Downloads/R-3777978-1344032418-8379.jpeg.jpg -i /Users/martin/Downloads/output-871140.mp3 -y -acodec copy -b:a 320k -vcodec libx264 -b:v 8000k -maxrate 8000k -minrate 8000k -bufsize 3M -filter:v scale=w=1920:h=1954 -preset medium -tune stillimage -crf 18 -pix_fmt yuv420p -shortest /Users/martin/Downloads/concatVideo-871140.mp4
ffmpeg version git-2021-03-24-13335df Copyright (c) 2000-2021 the FFmpeg developers
 built with Apple LLVM version 10.0.1 (clang-1001.0.46.4)
 configuration: --pkgconfigdir=/Users/martinbarker/Documents/projects/rendertune-0.5.0/workspace/lib/pkgconfig --prefix=/Users/martinbarker/Documents/projects/rendertune-0.5.0/workspace --pkg-config-flags=--static --extra-cflags='-I/Users/martinbarker/Documents/projects/rendertune-0.5.0/workspace/include -mmacosx-version-min=10.10' --extra-ldflags='-L/Users/martinbarker/Documents/projects/rendertune-0.5.0/workspace/lib -mmacosx-version-min=10.10' --extra-libs='-lpthread -lm' --enable-static --disable-securetransport --disable-debug --disable-shared --disable-ffplay --disable-lzma --disable-doc --enable-version3 --enable-pthreads --enable-runtime-cpudetect --enable-avfilter --enable-filters --disable-libxcb --enable-gpl --enable-nonfree --disable-libass --enable-libfdk-aac --enable-libmp3lame --enable-libx264
 libavutil 56. 66.100 / 56. 66.100
 libavcodec 58.128.100 / 58.128.100
 libavformat 58. 69.100 / 58. 69.100
 libavdevice 58. 12.100 / 58. 12.100
 libavfilter 7.107.100 / 7.107.100
 libswscale 5. 8.100 / 5. 8.100
 libswresample 3. 8.100 / 3. 8.100
 libpostproc 55. 8.100 / 55. 8.100
Input #0, image2, from '/Users/martin/Downloads/R-3777978-1344032418-8379.jpeg.jpg':
 Duration: 00:00:00.50, start: 0.000000, bitrate: 1758 kb/s
 Stream #0:0: Video: mjpeg (Progressive), yuvj444p(pc, bt470bg/unknown/unknown), 590x600 [SAR 1:1 DAR 59:60], 2 fps, 2 tbr, 2 tbn, 2 tbc
Input #1, mp3, from '/Users/martin/Downloads/output-871140.mp3':
 Metadata:
 title : My Little Grass Shack
 album : Our Hawaii - A Collection Of Personal Favorites
 artist : Society Of Seven
 track : 11
 encoder : Lavf58.69.100
 Duration: 00:06:25.59, start: 0.025057, bitrate: 320 kb/s
 Stream #1:0: Audio: mp3, 44100 Hz, stereo, fltp, 320 kb/s
 Metadata:
 encoder : Lavc58.12
Stream mapping:
 Stream #0:0 -> #0:0 (mjpeg (native) -> h264 (libx264))
 Stream #1:0 -> #0:1 (copy)
Press [q] to stop, [?] for help
[swscaler @ 0x7fbad9167600] deprecated pixel format used, make sure you did set range correctly
[libx264 @ 0x7fbad9040400] using SAR=2681/2679
dyld: lazy symbol binding failed: Symbol not found: ____chkstk_darwin
 Referenced from: /Applications/RenderTune.app/Contents/Resources/ffmpeg
 Expected in: /usr/lib/libSystem.B.dylib

dyld: Symbol not found: ____chkstk_darwin
 Referenced from: /Applications/RenderTune.app/Contents/Resources/ffmpeg
 Expected in: /usr/lib/libSystem.B.dylib

 at makeError (/Applications/Render…eca/lib/error.js:59)
 at handlePromise (/Applications/Render…/execa/index.js:114)
 at async file:/Applicat…js/newindex.js:1323



These files will render fine on windows/linux and recent mac versions. In order to package ffmpeg in my electron app on mac computers I had to build a custom sandboxed version with no dynamically linked libraries. I have a .sh file that automatically downloads ffmpeg and builds it with all the necessary flags for mac computers.
https://github.com/MartinBarker/RenderTune/blob/master/buildffmpeg.sh
Inside this .sh file is where I compile ffmpeg using these flags :


./configure \
 --pkgconfigdir="$WORKSPACE/lib/pkgconfig" \
 --prefix=${WORKSPACE} \
 --pkg-config-flags="--static" \
 --extra-cflags="-I$WORKSPACE/include -mmacosx-version-min=${MACOS_MIN}" \
 --extra-ldflags="-L$WORKSPACE/lib -mmacosx-version-min=${MACOS_MIN}" \
 --extra-libs="-lpthread -lm" \
 --enable-static \
 --disable-securetransport \
 --disable-debug \
 --disable-shared \
 --disable-ffplay \
 --disable-lzma \
 --disable-doc \
 --enable-version3 \
 --enable-pthreads \
 --enable-runtime-cpudetect \
 --enable-avfilter \
 --enable-filters \
 --disable-libxcb \
 --enable-gpl \
 --enable-nonfree \
 --disable-libass \
 --enable-libfdk-aac \
 --enable-libmp3lame \
 --enable-libx264 



If I try to run this script in my High Sierra VM, it fails with this message :


Unknown option "-extra-libs=-lpthread"


if I remove that flag it fails with a different message :


Unknown option "--enable-static"


I need this flag in order to release my electron app on the mac apple store, can anyone help me compile a static version of ffmpeg that works on old versions like High Sierra 10.13 as well as works on modern mac os systems ?