diff --git a/adapter/azure/processor.go b/adapter/azure/processor.go
index 797f652..3b0e30e 100644
--- a/adapter/azure/processor.go
+++ b/adapter/azure/processor.go
@@ -20,7 +20,7 @@ func formatMessages(props *ChatProps) interface{} {
 						return nil
 					}
 
-					props.Buffer.AddImage(obj)
+					props.Buffer.AddImage(obj, url)
 
 					return &MessageContent{
 						Type: "image_url",
diff --git a/adapter/chatgpt/processor.go b/adapter/chatgpt/processor.go
index 29baa48..668571a 100644
--- a/adapter/chatgpt/processor.go
+++ b/adapter/chatgpt/processor.go
@@ -18,7 +18,7 @@ func formatMessages(props *ChatProps) interface{} {
 					if err != nil {
 						globals.Info(fmt.Sprintf("cannot process image: %s (source: %s)", err.Error(), url))
 					} else {
-						props.Buffer.AddImage(obj)
+						props.Buffer.AddImage(obj, url)
 					}
 
 					return &MessageContent{
diff --git a/utils/buffer.go b/utils/buffer.go
index 483383a..16d0f3b 100644
--- a/utils/buffer.go
+++ b/utils/buffer.go
@@ -58,10 +58,15 @@ func (b *Buffer) GetChunk() string {
 	return b.Latest
 }
 
-func (b *Buffer) AddImage(image *Image) {
+func (b *Buffer) AddImage(image *Image, source string) {
 	b.Images = append(b.Images, *image)
 
-	b.Quota += float32(image.CountTokens(b.Model)) * b.Charge.GetInput()
+	if b.Charge.IsBillingType(globals.TokenBilling) {
+		b.Quota += float32(image.CountTokens(b.Model)) * b.Charge.GetInput()
+
+		// remove tokens from image source
+		b.Quota -= CountInputToken(b.Charge, b.Model, []globals.Message{{Content: source, Role: globals.User}})
+	}
 }
 
 func (b *Buffer) GetImages() Images {