mtmd: Add dynamic high-resolution image preprocessing for InternVL model (ggml-org#20847)

* added support for internvl's dynamic high-resolution (Qianfan-OCR needed)

* add min/max dynamic patch to gguf meta

* clean up

* simplified handling min/max dynamic patch

* reuse llava_uhd logic for slice images

* provide default values for older models

* flake8

* prevent writing 0 value to gguf

* remove duplicated resolution candidates with a better algorithm

* fix indentation

* format

* add protection from divide by zero

* change to 0 to be safe

---------

Co-authored-by: Xuan Son Nguyen <son@huggingface.co>

Author: bssrdf

convert_hf_to_gguf.py

@@ -4273,6 +4273,16 @@ def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None) -> Iter
 
 @ModelBase.register("InternVisionModel")
 class InternVisionModel(MmprojModel):
+
+    min_dynamic_tiles: int = 0
+    max_dynamic_tiles: int = 0
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        assert self.hparams_vision is not None
+        self.min_dynamic_tiles = self.global_config.get("min_dynamic_patch", 0)
+        self.max_dynamic_tiles = self.global_config.get("max_dynamic_patch", 0)
+
     def set_gguf_parameters(self):
         assert self.hparams_vision is not None
         if isinstance(self.hparams_vision['image_size'], list):
@@ -4295,6 +4305,11 @@ def set_gguf_parameters(self):
         downsample_ratio = self.global_config.get("downsample_ratio")
         assert downsample_ratio is not None
         self.gguf_writer.add_vision_projector_scale_factor(int(1.0 / downsample_ratio))
+        # older models may not have min/max_dynamic_patch in config
+        if self.min_dynamic_tiles > 0:
+            self.gguf_writer.add_vision_preproc_min_tiles(self.min_dynamic_tiles)
+        if self.max_dynamic_tiles > 0:
+            self.gguf_writer.add_vision_preproc_max_tiles(self.max_dynamic_tiles)
 
     def tensor_force_quant(self, name, new_name, bid, n_dims):
         if ".position_embd." in new_name:

gguf-py/gguf/constants.py

@@ -301,6 +301,8 @@ class ClipVision:
         IMAGE_SIZE          = "clip.vision.image_size"
         IMAGE_MIN_PIXELS    = "clip.vision.image_min_pixels"
         IMAGE_MAX_PIXELS    = "clip.vision.image_max_pixels"
+        PREPROC_MIN_TILES   = "clip.vision.preproc_min_tiles"
+        PREPROC_MAX_TILES   = "clip.vision.preproc_max_tiles"
         PREPROC_IMAGE_SIZE  = "clip.vision.preproc_image_size"
         PATCH_SIZE          = "clip.vision.patch_size"
         EMBEDDING_LENGTH    = "clip.vision.embedding_length"

gguf-py/gguf/gguf_writer.py

@@ -1156,6 +1156,12 @@ def add_vision_max_pixels(self, value: int) -> None:
     def add_vision_min_pixels(self, value: int) -> None:
         self.add_uint32(Keys.ClipVision.IMAGE_MIN_PIXELS, value)
 
+    def add_vision_preproc_max_tiles(self, value: int) -> None:
+        self.add_uint32(Keys.ClipVision.PREPROC_MAX_TILES, value)
+
+    def add_vision_preproc_min_tiles(self, value: int) -> None:
+        self.add_uint32(Keys.ClipVision.PREPROC_MIN_TILES, value)
+
     def add_vision_preproc_image_size(self, value: int) -> None:
         self.add_uint32(Keys.ClipVision.PREPROC_IMAGE_SIZE, value)
 

tools/mtmd/clip-impl.h

@@ -38,6 +38,8 @@
 #define KEY_IMAGE_SIZE          "clip.vision.image_size"
 #define KEY_IMAGE_MIN_PIXELS    "clip.vision.image_min_pixels"
 #define KEY_IMAGE_MAX_PIXELS    "clip.vision.image_max_pixels"
+#define KEY_PREPROC_MIN_TILES   "clip.vision.preproc_min_tiles"
+#define KEY_PREPROC_MAX_TILES   "clip.vision.preproc_max_tiles"
 #define KEY_PREPROC_IMAGE_SIZE  "clip.vision.preproc_image_size"
 #define KEY_PATCH_SIZE          "clip.vision.patch_size"
 #define KEY_IMAGE_MEAN          "clip.vision.image_mean"

tools/mtmd/clip-model.h

@@ -42,6 +42,9 @@ struct clip_hparams {
     int32_t image_max_pixels = -1;
     int32_t n_merge = 0; // number of patch merges **per-side**
 
+    int32_t preproc_min_tiles = 0;
+    int32_t preproc_max_tiles = 0;
+
     float image_mean[3];
     float image_std[3];
 

tools/mtmd/clip.cpp

@@ -1138,6 +1138,16 @@ struct clip_model_loader {
                         }
                     } break;
                 case PROJECTOR_TYPE_INTERNVL:
+                    {
+                        // older version of internvl doesn't have min/max tiles, we need to provide default values for them to avoid issues
+                        hparams.preproc_min_tiles = 1;
+                        hparams.preproc_max_tiles = 12;
+                        get_u32(KEY_PROJ_SCALE_FACTOR, hparams.n_merge, false);
+                        get_u32(KEY_PREPROC_MIN_TILES, hparams.preproc_min_tiles, false);
+                        get_u32(KEY_PREPROC_MAX_TILES, hparams.preproc_max_tiles, false);
+                        GGML_ASSERT(hparams.preproc_min_tiles <= hparams.preproc_max_tiles && hparams.preproc_max_tiles < INT32_MAX);
+                        set_internvl_dhr_res_candidates(model);
+                    } break;
                 case PROJECTOR_TYPE_NEMOTRON_V2_VL:
                     {
                         get_u32(KEY_PROJ_SCALE_FACTOR, hparams.n_merge, false);
@@ -2188,6 +2198,27 @@ struct clip_model_loader {
             }
         }
     }
+
+    static void set_internvl_dhr_res_candidates(clip_model & model) {
+        auto & hparams = model.hparams;
+        int min_num = hparams.preproc_min_tiles;
+        int max_num = hparams.preproc_max_tiles;
+        if (min_num < 1) {
+           return; // avoid  divide by 0
+        }
+        for (int a = min_num; a <= max_num; ++a) {
+            int b_lo = (min_num + a - 1) / a;
+            int b_hi = max_num / a;
+            b_lo = std::max(b_lo, min_num);
+            b_hi = std::min(b_hi, max_num);
+            for (int b = b_lo; b <= b_hi; ++b) {
+                hparams.image_res_candidates.push_back(clip_image_size {
+                    a*hparams.image_size,
+                    b*hparams.image_size,
+                });
+            }
+        }
+    }
 };
 
 struct clip_init_result clip_init(const char * fname, struct clip_context_params ctx_params) {
@@ -2734,17 +2765,22 @@ struct llava_uhd {
         return res;
     }
 
-    static std::vector<clip_image_u8_ptr> slice_image(const clip_image_u8 * img, const slice_instructions & inst) {
+    static std::vector<clip_image_u8_ptr> slice_image(const clip_image_u8 * img, const slice_instructions & inst, bool overview_first = true) {
         std::vector<clip_image_u8_ptr> output;
 
         // resize to overview size
         clip_image_u8_ptr resized_img(clip_image_u8_init());
         img_tool::resize(*img, *resized_img, inst.overview_size, inst.interpolation_overview,
                          inst.padding_overview, inst.pad_color_overview);
-        output.push_back(std::move(resized_img));
+        if (overview_first) {
+            output.push_back(std::move(resized_img));
+        }
 
         if (inst.slices.empty()) {
             // no slices, just return the resized image
+            if (!overview_first) {
+                output.push_back(std::move(resized_img));
+            }
             return output;
         }
 
@@ -2765,6 +2801,10 @@ struct llava_uhd {
             output.push_back(std::move(img_slice));
         }
 
+        if (!overview_first) {
+            output.push_back(std::move(resized_img));
+        }
+
         return output;
     }
 
@@ -3149,10 +3189,20 @@ bool clip_image_preprocess(struct clip_ctx * ctx, const clip_image_u8 * img, str
                 res_imgs->grid_x = instructions.grid_size.width;
                 res_imgs->grid_y = instructions.grid_size.height;
             } break;
+        case PROJECTOR_TYPE_INTERNVL: // support dynamic high-resolution
+            {
+                GGML_ASSERT(!params.image_res_candidates.empty());
+                auto const inst = llava_uhd::get_slice_instructions(ctx, original_size);
+                std::vector<clip_image_u8_ptr> imgs = llava_uhd::slice_image(img, inst, false);
 
+                for (size_t i = 0; i < imgs.size(); ++i) {
+                    clip_image_f32_ptr res(clip_image_f32_init());
+                    normalize_image_u8_to_f32(*imgs[i], *res, params.image_mean, params.image_std);
+                    res_imgs->entries.push_back(std::move(res));
+                }
+            } break;
         case PROJECTOR_TYPE_GLM_EDGE:
         case PROJECTOR_TYPE_GEMMA3:
-        case PROJECTOR_TYPE_INTERNVL: // TODO @ngxson : support dynamic resolution
         case PROJECTOR_TYPE_NEMOTRON_V2_VL:
             {
                 clip_image_u8 resized_image;

tools/mtmd/mtmd.cpp

@@ -851,13 +851,15 @@ int32_t mtmd_encode(mtmd_context * ctx, const mtmd_image_tokens * image_tokens)
         LOG_ERR("%s: this API does not support non-vision input, please use mtmd_encode_chunk instead\n", __func__);
         return 1;
     }
+    auto proj_type = clip_get_projector_type(ctx_clip);
     int n_mmproj_embd = clip_n_mmproj_embd(ctx_clip);
     ctx->image_embd_v.resize(image_tokens->n_tokens() * n_mmproj_embd);
     bool ok = false;
 
     if (clip_is_llava(ctx_clip)
         || clip_is_minicpmv(ctx_clip)
-        || clip_is_glm(ctx_clip)) {
+        || clip_is_glm(ctx_clip)
+        || proj_type == PROJECTOR_TYPE_INTERNVL) {
         // TODO @ngxson : llava does not support batched encoding ; this should be fixed inside clip_image_batch_encode()
         const auto & entries = image_tokens->batch_f32.entries;
         for (size_t i = 0; i < entries.size(); i++) {