Image Generation for gemini-nano-banana-2.1

curl --location 'https://api.key4u.vn/v1beta/models/gemini-nano-banana-2.1:generateContent' \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '{
  "contents": [
    {
      "parts": [
        {
          "text": "Completely replace the face and hair of the person in Figure 2 with those of the person in Figure 1: the facial features and facial details must come entirely from Figure 1, with none of Figure 2'\''s facial characteristics retained; adjust the face angle to match the head pose in Figure 2; keep the clothing, body except for hair accessories, and background in Figure 2 unchanged; blend the skin tone, lighting, and shadows naturally, with no visible compositing seams; photorealistic style."
        },
        {
          "text": "Reference Image 1 (\"Image 1\" in the prompt):"
        },
        {
          "inlineData": {
            "data": "<Base64 of Figure 1, excluding the data:image/jpeg;base64, prefix>",
            "mimeType": "image/jpeg"
          }
        },
        {
          "text": "Reference Figure 2 (\"Figure 2\" in the prompt):"
        },
        {
          "inlineData": {
            "data": "<Base64 of Figure 2, excluding the data:image/jpeg;base64, prefix>",
            "mimeType": "image/jpeg"
          }
        }
      ],
      "role": "user"
    }
  ],
  "generationConfig": {
    "imageConfig": {
      "aspectRatio": "3:4",
      "imageSize": "2K"
    },
    "responseModalities": [
      "TEXT",
      "IMAGE"
    ]
  },
  "response_format": "base64"
}'