ZCompr把 Nikon ZR 的 RAW 影片縮小，
輸出仍然是 RAW。
Shrink Nikon ZR RAW video.
It stays RAW.
ZCompr 重新編碼 N-RAW（.NEV）與 R3D NE（.R3D）檔案內的影像資料，容器、metadata、時間碼與音訊原樣保留。檔案小 25% 到 65%，仍然能在 DaVinci Resolve 裡當 RAW 調色。
ZCompr re-encodes the image data inside N-RAW (.NEV) and R3D NE (.R3D) files and leaves the container, metadata, timecode and audio untouched. Files get 25 to 65 percent smaller and still grade as RAW in DaVinci Resolve.
為什麼需要
Why
ZR 的 6K R3D NE 是固定碼率，每一幀都是 7,750,656 bytes。
The ZR's 6K R3D NE is constant bitrate: every frame is 7,750,656 bytes.
6060 × 3410，23.976 fps 的寫入速度
at 6060 × 3410, 23.976 fps
每一分鐘；實測 1437 幀（60 秒）的片段是 11.14 GB
per minute; a real 1437-frame (60 s) clip is 11.14 GB
每一小時。一天的拍攝很容易就是幾 TB
per hour. A day of shooting runs to several TB
轉成 ProRes 或 H.265 可以變小，但白平衡、ISO、曝光就被烤進去了，調色時沒有 RAW 的餘裕。ZCompr 的做法不一樣：它在 RAW 的層級重新量化，變小之後還是 RAW，開起來和原檔一樣。
Converting to ProRes or H.265 makes files smaller, but white balance, ISO and exposure get baked in and you lose RAW latitude in the grade. ZCompr works differently: it re-quantizes at the RAW level, so the smaller file is still RAW and opens exactly like the original.
R3D NE 其實是什麼
What R3D NE actually is
名字裡有 R3D，但它不是 RED 以前的 REDCODE RAW。
It has R3D in the name, but it is not RED's earlier REDCODE RAW.
- 它是 RAW。裡面是感光元件的 Bayer 原始資料，用 TICO RAW（JPEG XS 的一種）編碼。白平衡、ISO、曝光都還沒決定。
- 它不是 REDCODE RAW。RED 自家機身的 R3D 用的是 REDCODE 小波編碼；ZR 的 R3D NE 是 TICO RAW 裝進 R3D 容器。RED SDK 把它列為另一種檔案類型，也不支援 GPU 解碼。
- 它和 N-RAW（.NEV）是同一份資料。ZR 錄的 R3D NE 與 N-RAW 影像資料完全相同，只有外層標籤不同：codec 標籤、gamma 與色域（N-Log＋Rec.2020 對 Log3G10＋REDWideGamutRGB）、RED 的片段 metadata。兩者互轉只改標籤，來回一趟影像一模一樣。
- 為什麼有人選 R3D NE 拍？因為它能走 RED 的 IPP2 色彩管線與工具：REDCINE-X PRO、DaVinci Resolve 的 RED 解碼器、RMD 設定檔、Log3G10／REDWideGamutRGB 的工作流程。調色「彈性」和 N-RAW 一樣多，多的是這一套工具。
- It is RAW. Inside is the sensor's Bayer data, encoded with TICO RAW (a JPEG XS variant). White balance, ISO and exposure are not decided yet.
- It is not REDCODE RAW. R3D files from RED's own cameras use REDCODE wavelet coding; the ZR's R3D NE is TICO RAW inside an R3D container. The RED SDK lists it as a separate file type and does not GPU-decode it.
- It is the same data as N-RAW (.NEV). R3D NE and N-RAW recorded by the ZR carry identical image data; only the outer labels differ: the codec tag, gamma and gamut (N-Log + Rec.2020 vs Log3G10 + REDWideGamutRGB), and RED's clip metadata. Converting one to the other only rewrites labels, and a round trip gives back identical pixels.
- So why shoot R3D NE? Because it goes through RED's IPP2 colour pipeline and tools: REDCINE-X PRO, the RED decoder in DaVinci Resolve, RMD sidecars, the Log3G10 / REDWideGamutRGB workflow. The grading latitude is the same as N-RAW; what you gain is that toolset.
這對壓縮的意義：既然兩種檔案都是 TICO RAW，就可以直接重新量化裡面的係數，不用經過 RED 或 Nikon 的 SDK，也不用先解成影像再重編。ZCompr 兩種都收，輸出和輸入同一種格式。
What this means for compression: since both files are TICO RAW, the coefficients inside can be re-quantized directly, without the RED or Nikon SDKs and without decoding to pixels and re-encoding. ZCompr takes both and writes the same format it was given.
以上依 RED R3D SDK 9.2.1 的文件與我們對 ZR 片段的實測整理；格式細節參考了社群對 TICO RAW／JPEG XS 位元流的公開研究。
Based on the RED R3D SDK 9.2.1 documentation and our own measurements of ZR clips; format details draw on published community research into the TICO RAW / JPEG XS bitstream.
怎麼壓、壓多少
How it compresses, and how much
四個檔位，以原檔的 bpp（每像素位元數）為基準；也可以拉滑桿自己設。ZR 原生是 3.00 bpp。
Four presets, expressed as a fraction of the original bpp (bits per pixel); or set your own with the slider. The ZR records at 3.00 bpp.
| 檔位 | Preset | bpp | 影像資料大小 | Image data size | 說明 | Notes |
|---|---|---|---|---|---|---|
| Lossless | = 原檔source | −4% | 只重新封裝、去掉相機的填充；每個像素解出來完全相同。實測 6K R3D NE 2.14 GB → 2.05 GB | Repack only and drop the camera's padding; every decoded pixel is identical. Measured on 6K R3D NE: 2.14 GB → 2.05 GB | ||
| Light | × 0.75 | ≈ −25% | 預設。日常素材看不出差別 | Default. Indistinguishable on everyday footage | ||
| Medium | × 0.55 | ≈ −45% | 主力歸檔檔位 | The archiving workhorse | ||
| Strong | × 0.35 | ≈ −65% | 實測 243 幀的 6K 片段 1.89 GB → 694 MB（−63%），Resolve 正常開啟 | Measured: a 243-frame 6K clip went 1.89 GB → 694 MB (−63%) and opens normally in Resolve |
壓之前先看
Look before you commit
預覽視窗並排或分割比對原檔與壓縮後的畫面，可放大到 100%、400%。
The preview compares the original and the compressed frame side by side or split, zoomable to 100% and 400%.
σ 差異圖
σ difference map
把壓縮造成的誤差畫成「原幀本身雜訊的幾倍」，在 14-bit 的感光元件資料上計算，不是在算繪後的 RGB 上。1σ 以下表示誤差淹沒在雜訊裡。
Shows the compression error as a multiple of the frame's own noise, computed on the 14-bit sensor data rather than rendered RGB. Below 1σ the error is buried in the noise.
也能轉 H.265
H.265 too
需要代理檔或交片時，用 RED 的 IPP2 管線顯影成 10-bit HEVC（.mp4），6K 或 4K，曝光、白平衡、ISO 都可調，支援 N-Log 與 Log3G10 輸出。
For proxies or delivery, develop through RED's IPP2 pipeline to 10-bit HEVC (.mp4) at 6K or 4K, with exposure, white balance and ISO controls and N-Log or Log3G10 output.
上圖：Strong 檔位的 σ 差異圖，色條 0.5σ 到 2σ；這一幀 7.7 MB → 2.8 MB（−63.4%）。
Above: the σ difference map at the Strong preset, colour bar 0.5σ to 2σ; this frame went 7.7 MB → 2.8 MB (−63.4%).
怎麼用
How to use it
全部在你的 Mac 上完成，檔案不會上傳到任何地方。
Everything runs on your Mac; nothing is uploaded anywhere.
安裝
Install
下載 ZCompr.dmg，打開後把 ZCompr 拖進「應用程式」。已經過 Apple 公證，直接雙擊就能開。
Download ZCompr.dmg, open it and drag ZCompr into Applications. It is notarized by Apple, so it opens with a double-click.
加入片段
Add clips
把 .NEV 或 .R3D 檔（或整個資料夾）拖進視窗。清單會列出格式、尺寸、幀數、大小與原生 bpp。
Drag .NEV or .R3D files (or whole folders) into the window. The list shows format, size, frame count, file size and native bpp.
選檔位，看預覽
Pick a preset, check the preview
RAW 模式選 Lossless／Light／Medium／Strong 或拉滑桿；點縮圖進預覽比對。H.265 模式調顯影參數。
In RAW mode choose Lossless / Light / Medium / Strong or drag the slider; click a thumbnail to compare in the preview. In H.265 mode adjust the development settings.
選輸出位置
Choose where output goes
子資料夾、原檔旁（可自訂檔名格式）或指定資料夾。可勾選「完成後把原檔移到垃圾桶」。
A subfolder, beside the original (with a custom name format) or a fixed folder. Optionally move originals to the Trash when done.
開始
Start
按「開始壓縮」。進度、fps 與剩餘時間即時顯示；完成後清單顯示省了多少。
Press Start. Progress, fps and time remaining update live; when done the list shows how much you saved.
監看資料夾（選用）
Watch folders (optional)
指定幾個資料夾，新片段寫入穩定後自動用你設好的檔位壓縮，可登入時自動啟動、在選單列顯示狀態。
Point it at folders; new clips are compressed automatically with the preset you chose once they stop changing. It can launch at login and shows status in the menu bar.
測試版的規則：每台 Mac 從第一次按「開始」起 30 天；到期後 app 還能打開看片段，但不能壓縮、轉檔與監看，到同一個網址拿新版再按一次開始就好。只處理拍攝時間在現在以前的片段。有想法請用「輔助說明」選單的「意見回饋…」告訴我們。
Beta rules: each Mac gets 30 days from the first time you press Start; after that the app still opens and shows clips but will not compress, convert or watch until you download the new version from the same address and press Start again. Only clips recorded before now are processed. Send ideas through Help → Send Feedback.