Beta 0.4.4 · Windows · 12 languages · installer or portable zip (no Python needed) · from source: Python 3.10+, standard library only

Video · Видео на русском · Screenshots · Download · Getting started · Releases

Русский язык. Окно программы и установщик есть на русском: язык выбирается в установщике и в Настройки → Язык. Переводы сделаны машинным способом и не проверялись носителями языка, поэтому возможны ошибки; исправления приветствуются (см. CONTRIBUTING.md). Описание на этой странице и документация в docs/ пока только на английском. Видео-обзор на русском.

I started this because the Modern Warfare campaign on my PC looked blurry no matter what I did in the graphics menu. Walls and character gear sat on the lowest texture tier even with every setting maxed out. The game is supposed to download higher-resolution texture pieces from a CDN while you play, and on my machine it never did. This repository is what came out of tracking that down: a short explanation of the bug, and a set of small tools that work around it.

Please read this first. This is research / proof-of-concept code. The repository contains source code and written notes only: no Activision files, game assets, game binaries, CDN content, keys or chunk catalogues, and none will ever be shared here. Please don't attach any to issues or pull requests. The tools only read files from your own installation and only request public, unauthenticated URLs that the game itself requests. They don't patch, hook or read the memory of the game, its launcher, drivers or anti-cheat, and they don't get around any licensing, DRM or login. I wrote them to help the game load its own higher-detail textures: they deliver only the texture files the game asks for, and nothing that touches gameplay or gives anyone an advantage over other players. They were built and tested on the single-player campaign; multiplayer and HQ (cod.exe) are experimental, see below. Using them is your decision and your responsibility. Downloading game content in bulk, editing your hosts file and routing the game through a local proxy may go against the game's terms of service, or the law where you live. This project is not affiliated with or endorsed by Activision. "Call of Duty" and "Modern Warfare" are trademarks of their owners and appear here only to say what the tools are for. No warranty (see LICENSE and DISCLAIMER.md).

I made a short video (about five and a half minutes) that goes through the whole thing: what's wrong with the texture lookup, how the fix works, how to install the program, and then the new main window from the first start to a finished session, the Settings, the offline copy and Advanced mode. It should play right here. If it doesn't load for you, you can download the file from the 0.3.0-beta release (about 65 MB).

The program window in it is the real thing (version 0.3.0-beta, demo numbers, a throw-away folder), next to a few simple diagrams and the two in-game frames, with captions on top. The voice is computer-generated, and so are the music and sound effects, so don't expect a polished production. The in-game frames were taken with the earlier window design and aren't a measured before/after comparison, and the game art belongs to its owners.

Тот же обзор на русском языке (около семи минут): окно программы, установщик, подписи и закадровый голос. Видео должно воспроизводиться прямо здесь. Если оно не загружается, скачайте файл из релиза 0.4.0-beta (около 75 МБ).

В видео показано настоящее окно программы (версия 0.4.0-beta, демонстрационные числа, временная папка), рядом с несколькими простыми схемами и двумя кадрами из игры, с подписями поверх. Голос, музыка и звуки созданы компьютером (голос — Piper, модель ru_RU-irina-medium, синтез без выхода в интернет), так что это не профессиональная постановка. Кадры из игры сняты с прежним дизайном окна и не являются точным сравнением «до и после»; игровая графика принадлежит её владельцам.

The installer starts in your Windows language (and offers a language list), asks whether to install for all users (the default: Program Files, one permission prompt) or for you only (no administrator rights), shows the notice and licence, says what it will and will not do, and offers the shortcuts. Cancelling at any point installs nothing.

The program. Screenshots of version 0.4.0-beta on Windows 11. They show demo numbers from a throw-away folder: no game was running, and there is no game imagery in them (the two in-game frames are further down). They are regenerated when the windows change (python tools\make_screenshots.py; the installer pages with python packaging\shoot_installer.py); the version in the title bar is the version they were taken with.

First start. A new user is asked three things: where the game is (the tool looks in the usual places and you confirm what it finds), how textures should load (while playing, or from an offline copy you download once) and, only if the game folder needs it, to make one small change in it (the game setup).

Home. One button. Turn on HD textures, start the game and keep the window open. The three small cards show the game folder, how textures load and the free space, and every part has a hover tip.

While you play: how many textures were delivered, the speed, how many requests failed, where the textures come from and a three-minute graph.

After the session: a short summary of what the game asked for and what was delivered. It says nothing about how the picture looks; the before/after test is for that.

Settings slide in from the right: how textures load, the offline copy, the game folder, the one-time game setup, the Doctor, the word list, reports, the before/after test, reduced motion and Advanced mode.

The offline copy has its own page: how much of the texture pack is on the PC, pause and resume, and two choices (campaign only or everything, and how detailed).

Advanced mode keeps every tab of the earlier window (Dashboard, Proxy, Texture pack, Mirror, Cache, Game, Doctor, Report, Hosts / DNS, Logs, Settings) behind a side navigation. Each page opens with its name and a line saying what it is for.

In Russian. The same screens with the Russian text (the program and the installer follow your Windows language, see Languages).

In the game. Two frames from a play session of the single-player campaign at 2560x1440 with the toolkit running (0.2.5-beta, so the window is the earlier design). In the first, the Dashboard sits next to the game: 117 texture pieces delivered so far, none from the internet, no errors (the game folder path in the window is covered). In the second, a close-up of a character and a shop interior. They show how the game looks with the streamed textures; they are not a measured comparison (I took no before/after pairs, see section 7 of FINDINGS). The frames are copyrighted game art, shown here only to illustrate the toolkit.

On a PC whose internet connection has no IPv6, the game's texture streamer looks up the CDN host name (cod-assets.cdn.callofduty.com) and only accepts an IPv6 answer. Windows hands it an IPv4 address wrapped as IPv6 (::ffff:a.b.c.d), and then refuses to open a socket to that address, so the game never sends a single packet. Nothing in the UI tells you. The cache folder just stays empty and you play on the shipped low-resolution textures.

Pointing the CDN host name at the loopback address in the hosts file and running a small local proxy that forwards the requests over IPv4 is enough to make the unmodified game start streaming. The whole story, with the captures that show it, is in docs/ISSUE-ipv6-cdn-lookup.md and docs/FINDINGS.md.

• Twelve languages (see Languages): the window and the installer follow your Windows language, or the one you pick.
• Hosts manager (tools/ccshosts.py): adds and removes the override in a clearly marked block, makes a backup before every change, reads the file back to check it, and rolls back if something is off. It needs administrator rights, which the program has (see Administrator rights).
• Proxy (tools/ccsproxy.py): listens on loopback, forwards chunk requests to the CDN, or serves them from a local mirror. It can also refuse chunks above a size you choose.
• Mirror (tools/ccsmirror.py): downloads the chunks once, checks each one (size and MD5 against the server's ETag), and can be paused and resumed. You can limit bandwidth, set a daily quota, pick a detail level, and it waits patiently if your connection drops. Defaults are deliberately gentle (4 connections, 50 requests per second, a User-Agent that names the tool, back-off on HTTP 429/503).
• Control window (tools/ccsgui.py; in the installer and the zip it is MW4 Texture Streaming.exe): a Home screen with one button for everyday use, and Advanced mode with one place for all of the above, plus a doctor that checks your setup, live statistics, and a report for every game session (what the game asked for, how fast, how much was already in its cache).
• First start and help in plain words: the Home screen finds your game folder, checks the PC and walks through the first run, with hover tips, cards that say what went wrong and what to press, and a before/after test. New here? See docs/GETTING-STARTED.md.
• Offline copy: choose what to download (campaign only or everything) and how large the pieces may be, pause and resume any time. Advanced mode's Texture pack tab has every option. See docs/TEXTURE-PACK.md.

The proxy and mirror never touch the game process. Details of how the pieces fit together are in docs/ARCHITECTURE.md.

Pick one. The files are on the Releases page (while the versions are betas they are marked Pre-release).

Windows may say "Windows protected your PC" (SmartScreen) because the files are not code-signed yet: choose More info, then Run anyway. You can check a download against SHA256SUMS.txt on the release page (certutil -hashfile <file> SHA256). Release files are built from the tagged source with packaging\build.bat (see CONTRIBUTING). The installer changes nothing in your hosts file; the program does that only when you press Turn on HD textures (Start session in Advanced mode).

You need a PC install of the game, Python 3.10 or newer with tkinter (the normal python.org installer has it), and a few GiB of free disk space at the very least. The full campaign set is around 82 GiB; a smaller "standard" level is about 54 GiB.

git clone https://github.com/voidfnc/mw4-texture-streaming-research
cd mw4-texture-streaming-research
python tools\ccsgui.py

On first start the window shows a short notice, then asks where your game is (you confirm what it finds), how textures should load and, if the game folder needs it, for one small change in it. It never changes anything without a click. After that the Home screen has one button, Turn on HD textures: press it, launch the game and watch the numbers. Settings (top right) lead to everything else, and Advanced mode shows every tab. New to all this? Start with docs/GETTING-STARTED.md: plain words, no command line, a list of what the terms mean. Nothing is assumed, and the settings live in tools\work\gui_settings.json. docs/USAGE.md walks through the Home screen and each Advanced tab, and the command-line versions of everything are listed there too. To undo the hosts change at any time run tools\restore-hosts.bat.

The tests don't need the game: python -m unittest discover -s tools/tests (about 300 tests, a few minutes).

The program asks for administrator permission when it starts (the Windows prompt, called UAC) and runs with it. It needs it for three things: the hosts file is protected, the game folder is often inside Program Files, where a normal user cannot write to a texture mirror or change the game's settings files, and the one-time Game setup changes files in the game folder. With the rights from the start, none of these asks again. It uses them only for what this README lists: the marked block in the hosts file, the game setup you confirm, and its own files. If you decline the prompt the program still starts and asks for permission for each hosts-file change, as before. From source, the window relaunches itself elevated once (CCS_NO_ELEVATE=1 or --no-elevate keeps it unelevated). The setup program itself runs without administrator rights.

Because the program runs elevated, whoever can change its files can make it run their code with those rights. That is why the installer's default is to install for all users (Program Files): only an administrator can change files there. If you choose "for me only", the files are inside your own profile and other programs that run as you could replace them; the portable zip has the same property, so keep it in a folder only you can write to.

Most problems show up as a card on the Home screen that says what happened and offers a button, and in Check my PC (Settings; it is the Doctor tab in Advanced mode), which tells you what is wrong and offers a fix. Problems that have come up:

"Permission denied" when the hosts file is written. Windows protects that file on purpose, and a write can be refused even when the window says it runs as administrator. The usual causes are the read-only attribute on the file (run attrib -r "%SystemRoot%\System32\drivers\etc\hosts" in an admin Command Prompt) or security software with hosts-file protection (pause it briefly or allow MW4 Texture Streaming.exe and ccs-cli.exe, or python.exe when running from source, apply the override, turn it back on). A refused write leaves the file untouched, and the message says so. I don't turn off anyone's security software and I don't change permissions on system files for you; that is your call. If you would rather not let the tool write the file at all, you can add the two lines yourself (ccs-cli.exe --ccs-run ccshosts diff apply, or python tools\ccshosts.py diff apply from source, shows them).

Textures are streamed (the report shows requests and answers) but still look low. In some game folders the Steam settings put the game in offline mode, and the game can look for its cache in sp26\xpak_cache while the engine fills xpak_cache. The Doctor's Game setup row (and the first-run step One small change in your game folder) fixes both after you confirm: it sets offline=0 and disable_lan_only=1 in sp26\steam_settings\configs.main.ini (a copy of the original is kept) and links sp26\xpak_cache to xpak_cache. Close the game first, and start it again afterwards. Details and the command line: docs/USAGE.md.

I built an offline copy. Can I play without the program? No. The game still asks for its textures through the helper, so each time you play: start the program, press Turn on HD textures, launch the game and keep the window open. The copy only means the pieces come from your disk instead of the internet; the game does not read it on its own. The copy is kept in the mirror folder (the Texture pack tab in Advanced mode shows where; by default a mirror folder inside the game folder). With the Default profile it is used first, and Use only this copy on the offline copy page (or Play offline (profile) on the Texture pack tab) makes sure nothing goes to the internet. The Dashboard's Mirror light (Advanced mode) shows how many pieces it found; "off" while a session runs means none were found, so check the Mirror folder in the Game tab of Advanced mode. The first-run question How should textures load? only changes what the window shows, and can be switched in Settings. More in docs/USAGE.md.

The counters stay at zero right after the game starts. In my sessions the game began asking for texture pieces once it had loaded into gameplay, not at the launcher or the main menu. Load a mission and give it a minute before judging; if the counters are still at zero a minute or two later, the Doctor tells you why.

"'NoneType' object has no attribute 'splitlines'" when starting a session. That was a bug on Windows installs with a non-English language, fixed in 0.1.1. Update to the latest version. If you still see it, open an issue with the support bundle from the Doctor tab (check its contents first).

The mirror downloads far slower than your line. Fixed in 0.1.2: older versions could end up on one fixed CDN address that may be far away. The tool now measures the candidate servers before a run and uses the fastest. Check the speed line on the Texture pack tab (it shows MiB/s and Mbps; 100 Mbps is about 11.9 MiB/s), set My line speed so it re-checks by itself, and see docs/TEXTURE-PACK.md. There is no hidden bandwidth cap.

More in docs/USAGE.md. To put your hosts file back to how it was, use Restore hosts (Start menu, or Restore hosts.bat next to the program; from source tools\restore-hosts.bat).

What I'm confident about: the transport bug exists on my machine and the fix works, meaning the game connects, requests chunks, gets them, and writes them into its own cache. In my longest session that was about 16,000 requests and 11 GiB, all answered, no errors.

What I'm less sure about:

• Whether the picture got better is partly my own eyes. Cutscenes looked much sharper to me afterwards, but I never ran a controlled before/after comparison.
• The detail-level cap (refusing large chunks) works at the proxy, but I only have a handful of observations of how the engine reacts to the refusal.
• The game asks again for many chunks that are already in its cache (roughly half of the ids in one session). I don't know why.
• Everything was developed and tested on one Windows PC and the single-player campaign. Multiplayer and HQ (cod.exe) are experimental: the tool recognises cod.exe, and it should work the same way if that part of the game asks the same server for its textures, but nobody has confirmed it yet. If you try it, please report what you see: Testing multiplayer / HQ.

The mirror can fetch the whole campaign set (about 82 GiB) or every package (about 111 GiB) from the publisher's servers. I kept that feature because it is the practical way to use the fix on a slow connection: download once, then play offline from disk. It also means you are copying someone else's game content in bulk, so before the first run the GUI (and the command line, with --accept-notice) shows a notice that you have to accept once per version. In short: the content belongs to the publisher, use it only with your own copy of the game, keep it on your PC, never share or re-host it, and check that bulk downloading is allowed where you live and under the game's terms. If you aren't comfortable with that, use only the hosts manager and the proxy without a mirror (profile Capture): they fix the lookup problem without downloading anything in advance.

The mirror can pull a lot of data from someone else's servers. Please download once and then play offline from the mirror, keep the default limits unless you have a reason, and don't host or share what you download. If the CDN ever asks the tool to slow down, it will.

The program and its installer speak English, Russian, Chinese (Simplified), Spanish, French, German, Portuguese (Brazil), Turkish, Polish, Japanese, Korean and Italian. The installer shows a language list first (it starts on your Windows display language), and the program follows that choice. To change it later: Settings, Language (Automatic follows Windows). The window restarts to apply it; a session that is running keeps running. Windows set to Traditional Chinese gets the Simplified Chinese text (there is no Traditional set yet). Logs, reports and file names stay in English so bug reports are easy to compare. The translations were drafted by machine and have not been proofread by native speakers: corrections are welcome as pull requests (see CONTRIBUTING.md).

English	Русский

Bug reports and ideas are welcome (CONTRIBUTING.md). Please never attach game files, chunk lists or captures that contain them. Security-related reports: see SECURITY.md.

MIT for the code in this repository. See LICENSE. It covers my code and notes only and gives no rights to any game, asset or trademark.