diff --git a/src/app/(dashboard)/images/page.tsx b/src/app/(dashboard)/images/page.tsx
index 5e3000c..4e4b8c6 100644
--- a/src/app/(dashboard)/images/page.tsx
+++ b/src/app/(dashboard)/images/page.tsx
@@ -10,7 +10,7 @@ import { useImages } from '@/hooks/useImages'
 import type { ImageItem } from '@/types/images'
 
 function ImagesPageInner() {
-  const { items, addFiles, setFeather, rotate, uploadOne, uploadAll, removeItem, assignProduct } = useImages()
+  const { items, addFiles, setFeather, setAlphaThreshold, rotate, uploadOne, uploadAll, removeItem, assignProduct } = useImages()
   const [lightboxItem, setLightboxItem] = useState<ImageItem | null>(null)
 
   return (
@@ -38,6 +38,7 @@ function ImagesPageInner() {
                 key={item.id}
                 item={item}
                 onFeatherChange={setFeather}
+                onAlphaThresholdChange={setAlphaThreshold}
                 onRotate={rotate}
                 onUpload={uploadOne}
                 onRemove={removeItem}
diff --git a/src/components/images/ImageCard.tsx b/src/components/images/ImageCard.tsx
index 1229b9a..bc5f639 100644
--- a/src/components/images/ImageCard.tsx
+++ b/src/components/images/ImageCard.tsx
@@ -5,6 +5,7 @@ import type { ImageItem } from '@/types/images'
 interface ImageCardProps {
   item: ImageItem
   onFeatherChange: (id: string, value: number) => void
+  onAlphaThresholdChange: (id: string, value: number) => void
   onRotate: (id: string, direction: 'cw' | 'ccw') => void
   onUpload: (id: string) => void
   onRemove: (id: string) => void
@@ -94,6 +95,7 @@ function ProductSearch({ itemId, onAssign }: { itemId: string; onAssign: (id: st
 export function ImageCard({
   item,
   onFeatherChange,
+  onAlphaThresholdChange,
   onRotate,
   onUpload,
   onRemove,
@@ -148,7 +150,7 @@ export function ImageCard({
           <ProductSearch itemId={item.id} onAssign={onAssignProduct} />
         )}
 
-        {/* Contrôles feather + rotation */}
+        {/* Contrôles feather + tolérance + rotation */}
         <div className={canAdjust ? '' : 'opacity-40 pointer-events-none'}>
           <label className="block text-xs text-slate-500 mb-1">
             Bords : {item.feather} px
@@ -163,6 +165,19 @@ export function ImageCard({
             className="w-full accent-indigo-500"
           />
 
+          <label className="block text-xs text-slate-500 mb-1 mt-2">
+            Tolérance verre : {item.alphaThreshold}
+          </label>
+          <input
+            type="range"
+            min={0}
+            max={100}
+            step={5}
+            value={item.alphaThreshold}
+            onChange={(e) => onAlphaThresholdChange(item.id, Number(e.target.value))}
+            className="w-full accent-amber-500"
+          />
+
           <div className="flex gap-1 mt-2">
             <button
               onClick={() => onRotate(item.id, 'ccw')}
diff --git a/src/hooks/useImages.ts b/src/hooks/useImages.ts
index 689b0b8..3a6f79e 100644
--- a/src/hooks/useImages.ts
+++ b/src/hooks/useImages.ts
@@ -90,7 +90,7 @@ export function useImages() {
 
   // Pipeline complet pour un item (avec ref)
   const runPipeline = useCallback(
-    async (id: string, blob: Blob, ref: string, feather: number, rotation: number) => {
+    async (id: string, blob: Blob, ref: string, feather: number, rotation: number, alphaThreshold: number) => {
       const { convertHeicToJpeg } = await import('@/lib/client/heicConverter')
       const { removeBackgroundRaw, compositeOnWhite } = await import('@/lib/client/bgRemover')
       const { rotateBlob } = await import('@/lib/client/imageRotator')
@@ -120,7 +120,7 @@ export function useImages() {
 
       let finalBlob: Blob
       try {
-        const composited = await compositeOnWhite(rawPng, feather)
+        const composited = await compositeOnWhite(rawPng, feather, alphaThreshold)
         finalBlob = await rotateBlob(composited, rotation)
       } catch (err) {
         update(id, { status: 'error', error: `Post-traitement : ${(err as Error).message}` })
@@ -133,15 +133,15 @@ export function useImages() {
     [update, searchProduct],
   )
 
-  // Recomposite rapide (feather ou rotation changés) — ne relance pas l'IA
+  // Recomposite rapide (feather, alphaThreshold ou rotation changés) — ne relance pas l'IA
   const recomposite = useCallback(
-    async (id: string, rawPngBlob: Blob, feather: number, rotation: number) => {
+    async (id: string, rawPngBlob: Blob, feather: number, rotation: number, alphaThreshold: number) => {
       const { compositeOnWhite } = await import('@/lib/client/bgRemover')
       const { rotateBlob } = await import('@/lib/client/imageRotator')
       try {
-        const composited = await compositeOnWhite(rawPngBlob, feather)
+        const composited = await compositeOnWhite(rawPngBlob, feather, alphaThreshold)
         const finalBlob = await rotateBlob(composited, rotation)
-        update(id, { processedBlob: finalBlob, feather, rotation })
+        update(id, { processedBlob: finalBlob, feather, rotation, alphaThreshold })
       } catch (err) {
         update(id, { status: 'error', error: `Retraitement : ${(err as Error).message}` })
       }
@@ -167,6 +167,7 @@ export function useImages() {
             processedBlob: null,
             rotation: 0,
             feather: 2,
+            alphaThreshold: 30,
             shopifyProductId: null,
             shopifyProductTitle: null,
             uploadedUrl: null,
@@ -176,7 +177,7 @@ export function useImages() {
           }))
           dispatch({ type: 'ADD', items: newItems })
           for (const item of newItems) {
-            runPipeline(item.id, item.originalBlob, item.ref, item.feather, item.rotation)
+            runPipeline(item.id, item.originalBlob, item.ref, item.feather, item.rotation, item.alphaThreshold)
           }
         } else {
           const ref = refFromFilename(file.name)
@@ -189,6 +190,7 @@ export function useImages() {
             processedBlob: null,
             rotation: 0,
             feather: 2,
+            alphaThreshold: 30,
             shopifyProductId: null,
             shopifyProductTitle: null,
             uploadedUrl: null,
@@ -197,7 +199,7 @@ export function useImages() {
             progress: null,
           }
           dispatch({ type: 'ADD', items: [newItem] })
-          runPipeline(newItem.id, newItem.originalBlob, newItem.ref, newItem.feather, newItem.rotation)
+          runPipeline(newItem.id, newItem.originalBlob, newItem.ref, newItem.feather, newItem.rotation, newItem.alphaThreshold)
         }
       }
     },
@@ -208,7 +210,16 @@ export function useImages() {
     (id: string, value: number) => {
       const item = items.find((i) => i.id === id)
       if (!item || !item.rawPngBlob) return
-      recomposite(id, item.rawPngBlob, value, item.rotation)
+      recomposite(id, item.rawPngBlob, value, item.rotation, item.alphaThreshold)
+    },
+    [items, recomposite],
+  )
+
+  const setAlphaThreshold = useCallback(
+    (id: string, value: number) => {
+      const item = items.find((i) => i.id === id)
+      if (!item || !item.rawPngBlob) return
+      recomposite(id, item.rawPngBlob, item.feather, item.rotation, value)
     },
     [items, recomposite],
   )
@@ -219,7 +230,7 @@ export function useImages() {
       if (!item || !item.rawPngBlob) return
       const delta = direction === 'cw' ? 90 : -90
       const newRotation = ((item.rotation + delta) % 360 + 360) % 360
-      recomposite(id, item.rawPngBlob, item.feather, newRotation)
+      recomposite(id, item.rawPngBlob, item.feather, newRotation, item.alphaThreshold)
     },
     [items, recomposite],
   )
@@ -269,5 +280,5 @@ export function useImages() {
     [update],
   )
 
-  return { items, addFiles, setFeather, rotate, uploadOne, uploadAll, removeItem, assignProduct }
+  return { items, addFiles, setFeather, setAlphaThreshold, rotate, uploadOne, uploadAll, removeItem, assignProduct }
 }
diff --git a/src/lib/client/bgRemover.ts b/src/lib/client/bgRemover.ts
index 963f0ab..75de2b8 100644
--- a/src/lib/client/bgRemover.ts
+++ b/src/lib/client/bgRemover.ts
@@ -38,8 +38,9 @@ export async function removeBackgroundRaw(
  * Composite un PNG transparent sur fond blanc avec feather optionnel.
  * @param pngBlob — PNG avec transparence (résultat de removeBackgroundRaw)
  * @param feather — récupération des bords en px (0 = strict, 5 = doux)
+ * @param alphaThreshold — pixels avec alpha > seuil deviennent opaques (0 = désactivé, ex: 30 pour récupérer le verre)
  */
-export function compositeOnWhite(pngBlob: Blob, feather: number): Promise<Blob> {
+export function compositeOnWhite(pngBlob: Blob, feather: number, alphaThreshold = 0): Promise<Blob> {
   const objectUrl = URL.createObjectURL(pngBlob)
 
   return new Promise((resolve, reject) => {
@@ -55,6 +56,16 @@ export function compositeOnWhite(pngBlob: Blob, feather: number): Promise<Blob>
 
       fgCtx.drawImage(img, 0, 0)
 
+      // Remonte les pixels semi-transparents (ex: verre) à pleine opacité
+      if (alphaThreshold > 0) {
+        const imageData = fgCtx.getImageData(0, 0, width, height)
+        const data = imageData.data
+        for (let i = 3; i < data.length; i += 4) {
+          if (data[i] > alphaThreshold) data[i] = 255
+        }
+        fgCtx.putImageData(imageData, 0, 0)
+      }
+
       if (feather > 0) {
         fgCtx.globalCompositeOperation = 'destination-over'
         fgCtx.filter = `blur(${feather}px)`
diff --git a/src/types/images.ts b/src/types/images.ts
index 9ea7b35..9946e0a 100644
--- a/src/types/images.ts
+++ b/src/types/images.ts
@@ -24,6 +24,7 @@ export interface ImageItem {
   processedBlob: Blob | null   // JPEG final sur fond blanc, pivoté (pour upload + vue "après")
   rotation: number             // 0, 90, 180, 270
   feather: number              // 0–5, défaut 2
+  alphaThreshold: number       // 0–100, défaut 30 — pixels semi-transparents rendus opaques
   shopifyProductId: string | null
   shopifyProductTitle: string | null
   uploadedUrl: string | null