clip : cap max image size 1024 for qwen vl model (ggml-org#13478)

Author: ngxson

tools/mtmd/clip.cpp

@@ -1909,16 +1909,20 @@ struct clip_model_loader {
                     } break;
                 case PROJECTOR_TYPE_QWEN2VL:
                     {
-                        // max image size = sqrt(max_pixels)
-                        // https://huggingface.co/Qwen/Qwen2-VL-7B-Instruct/blob/main/preprocessor_config.json
-                        hparams.image_size = 3584;
+                        // max image size = sqrt(max_pixels) = 3584
+                        // ref: https://huggingface.co/Qwen/Qwen2-VL-7B-Instruct/blob/main/preprocessor_config.json
+                        // however, the model use unreasonable memory past 1024 size, we force it to 1024 otherwise it's unusable
+                        // ref: https://huggingface.co/Qwen/Qwen2-VL-2B-Instruct/discussions/10
+                        hparams.image_size = 1024;
                         hparams.warmup_image_size = hparams.patch_size * 8;
                     } break;
                 case PROJECTOR_TYPE_QWEN25VL:
                     {
                         // max image size = sqrt(max_pixels)
                         // https://huggingface.co/Qwen/Qwen2.5-VL-7B-Instruct/blob/main/preprocessor_config.json
-                        hparams.image_size = 3584;
+                        // however, the model use unreasonable memory past 1024 size, we force it to 1024 otherwise it's unusable
+                        // ref: https://huggingface.co/Qwen/Qwen2-VL-2B-Instruct/discussions/10
+                        hparams.image_size = 1024;
                         hparams.warmup_image_size = hparams.patch_size * 8;
                         get_u32(KEY_WIN_ATTN_PATTERN, hparams.n_wa_pattern);
                     } break;