feat: generalize temporal tiling across video VAEs (#1926)

examples/common/common.cpp

@@ -1013,7 +1013,7 @@ ArgOptions SDGenerationParams::get_options() {
          &extra_sample_args},
         {"",
          "--extra-tiling-args",
-         "extra VAE tiling args, key=value list. LTX video VAE supports temporal_tile_frames (default: 4), temporal_tile_overlap (default: 1)",
+         "extra VAE tiling args, key=value list. Supported video VAEs accept temporal_tile_frames/temporal_tile_size (default: 4), temporal_tile_overlap (default: 1)",
          (int)',',
          &extra_tiling_args},
         {"",
@@ -1230,7 +1230,7 @@ ArgOptions SDGenerationParams::get_options() {
          &vae_tiling_params.enabled},
         {"",
          "--temporal-tiling",
-         "enable temporal tiling for LTX video VAE decode",
+         "enable temporal tiling for supported video VAE decode",
          true,
          &vae_tiling_params.temporal_tiling},
         {"",

examples/server/api.md

@@ -518,7 +518,8 @@ Shared default fields used by both `img_gen` and `vid_gen`:
 | `output_format` | `string` |
 | `output_compression` | `integer` |
 
-`vae_tiling_params.extra_tiling_args` accepts a key=value list. For LTX video VAE temporal tiling, `temporal_tile_frames` defaults to `4` and `temporal_tile_overlap` defaults to `1`.
+`vae_tiling_params.extra_tiling_args` accepts a key=value list. Supported video VAEs accept `temporal_tile_frames` (alias `temporal_tile_size`, default `4`) and `temporal_tile_overlap` (default `1`).
+LTX and Wan preserve causal state between temporal tiles. Hunyuan Video and TAEHV use overlap blending. MiniMax H3 keeps its model-specific fixed temporal windows because its latent-to-frame mapping is non-linear.
 
 `img_gen`-specific default fields:
 

src/core/backend_fit.cpp

@@ -364,15 +364,11 @@ namespace sd::backend_fit {
     }
 
     bool prepare_vae_decode_retry_tiling(sd_tiling_params_t& tiling_params, bool prefer_temporal_tiling) {
-        if (prefer_temporal_tiling) {
+        const char* retry_mode = nullptr;
-            if (tiling_params.temporal_tiling) {
+        if (prefer_temporal_tiling && !tiling_params.temporal_tiling) {
-                return false;
-            }
             tiling_params.temporal_tiling = true;
-        } else {
+            retry_mode                    = tiling_params.enabled ? "spatial+temporal" : "temporal";
-            if (tiling_params.enabled) {
+        } else if (!tiling_params.enabled) {
-                return false;
-            }
             tiling_params.enabled = true;
             if (tiling_params.tile_size_x <= 0) {
                 tiling_params.tile_size_x = 256;
@@ -380,10 +376,13 @@ namespace sd::backend_fit {
             if (tiling_params.tile_size_y <= 0) {
                 tiling_params.tile_size_y = 256;
             }
+            retry_mode = tiling_params.temporal_tiling ? "spatial+temporal" : "spatial";
+        } else {
+            return false;
         }
 
         LOG_WARN("auto-fit: VAE decode failed (likely out of memory); retrying with %s tiling",
-                 tiling_params.temporal_tiling ? "temporal" : "spatial");
+                 retry_mode);
         return true;
     }
 

src/model/vae/hunyuan_vae.hpp

@@ -758,6 +758,15 @@ namespace Hunyuan {
             return "hunyuan_video_vae";
         }
 
+        bool supports_temporal_tiling(VAETemporalDirection direction) const override {
+            return direction == VAETemporalDirection::DECODE;
+        }
+
+        int get_temporal_tile_output_scale(VAETemporalDirection direction) const override {
+            SD_UNUSED(direction);
+            return 4;
+        }
+
         void get_param_tensors(std::map<std::string, ggml_tensor*>& tensors) override {
             if (!decode_only) {
                 encoder.get_param_tensors(tensors, weight_prefix + ".encoder");

src/model/vae/ltx_vae.hpp

@@ -1213,9 +1213,6 @@ struct LTXVideoVAE : public VAE {
     static constexpr int DEFAULT_TEMPORAL_TILE_OVERLAP = 1;
 
     bool decode_only;
-    bool temporal_tiling_enabled = false;
-    int temporal_tile_frames     = DEFAULT_TEMPORAL_TILE_FRAMES;
-    int temporal_tile_overlap    = DEFAULT_TEMPORAL_TILE_OVERLAP;
     int ltx_vae_version;
     bool timestep_conditioning;
     int patch_size;
@@ -1248,64 +1245,24 @@ struct LTXVideoVAE : public VAE {
         return "ltx_video_vae";
     }
 
-    void set_temporal_tiling_enabled(bool enabled) override {
+    bool supports_temporal_tiling(VAETemporalDirection direction) const override {
-        temporal_tiling_enabled = enabled;
+        return direction == VAETemporalDirection::DECODE;
     }
 
-    void set_tiling_params(const sd_tiling_params_t& params) override {
+    int get_default_temporal_tile_frames(VAETemporalDirection direction) const override {
-        temporal_tiling_enabled = params.temporal_tiling;
+        SD_UNUSED(direction);
-        temporal_tile_frames    = DEFAULT_TEMPORAL_TILE_FRAMES;
+        return DEFAULT_TEMPORAL_TILE_FRAMES;
-        temporal_tile_overlap   = DEFAULT_TEMPORAL_TILE_OVERLAP;
+    }
 
-        for (const auto& [key, value] : parse_key_value_args(params.extra_tiling_args, "LTX VAE extra tiling arg")) {
+    int get_default_temporal_tile_overlap(VAETemporalDirection direction) const override {
-            int parsed = 0;
+        SD_UNUSED(direction);
-            if (!parse_strict_int(value, parsed)) {
+        return DEFAULT_TEMPORAL_TILE_OVERLAP;
-                LOG_WARN("ignoring invalid LTX VAE extra tiling arg '%s=%s'", key.c_str(), value.c_str());
-            } else if (key == "temporal_tile_frames") {
-                temporal_tile_frames = std::max(1, parsed);
-            } else if (key == "temporal_tile_overlap") {
-                temporal_tile_overlap = std::max(0, parsed);
-            } else {
-                LOG_WARN("ignoring unknown LTX VAE extra tiling arg '%s'", key.c_str());
-            }
-        }
     }
 
     void get_param_tensors(std::map<std::string, ggml_tensor*>& tensors) override {
         vae.get_param_tensors(tensors, weight_prefix);
     }
 
-    struct TemporalTilePlan {
-        int frames    = 1;
-        int overlap   = 0;
-        int stride    = 1;
-        int num_tiles = 1;
-    };
-
-    TemporalTilePlan resolve_temporal_tile_plan(int64_t total_frames) const {
-        TemporalTilePlan plan;
-        plan.frames  = std::max(1, temporal_tile_frames);
-        plan.overlap = std::max(0, temporal_tile_overlap);
-
-        if (plan.overlap >= plan.frames) {
-            LOG_WARN("temporal_tile_overlap (%d) is greater than or equal to temporal_tile_frames (%d), adjusting values to avoid empty decode windows",
-                     plan.overlap,
-                     plan.frames);
-            plan.overlap = plan.frames - 1;
-        }
-        if (total_frames > 1 && plan.overlap >= total_frames) {
-            LOG_WARN("temporal_tile_overlap (%d) is greater than or equal to total latent frames (%lld), adjusting values to decode at least one tile",
-                     plan.overlap,
-                     (long long)total_frames);
-            plan.overlap = static_cast<int>(total_frames - 1);
-        }
-
-        plan.stride          = std::max(1, plan.frames - plan.overlap);
-        int64_t tiled_frames = std::max<int64_t>(1, total_frames - plan.overlap);
-        plan.num_tiles       = total_frames > 0 ? static_cast<int>((tiled_frames + plan.stride - 1) / plan.stride) : 0;
-        return plan;
-    }
-
     std::string temporal_feat_cache_name(size_t feat_idx) const {
         return "ltx_vae_temporal_feat:" + std::to_string(feat_idx);
     }
@@ -1365,52 +1322,53 @@ struct LTXVideoVAE : public VAE {
 
     sd::Tensor<float> decode_temporal_tiled_streaming(const int n_threads,
                                                       const sd::Tensor<float>& input,
-                                                      size_t expected_dim) {
+                                                      size_t expected_dim,
+                                                      const VAETemporalTilingConfig& config) {
         const int64_t total_frames = input.shape()[2];
-        TemporalTilePlan plan      = resolve_temporal_tile_plan(total_frames);
+        auto plan                  = make_vae_temporal_tile_plan(total_frames, config);
 
         LOG_DEBUG("Using streaming temporal tiling: temporal_tile_frames=%d, temporal_tile_overlap=%d, total latent frames=%lld, resulting in %d tiles",
-                  plan.frames,
+                  plan.tile_frames,
                   plan.overlap,
                   (long long)total_frames,
-                  plan.num_tiles);
+                  (int)plan.tiles.size());
 
         free_cache_ctx_and_buffer();
         cache_tensor_map.clear();
 
-        sd::Tensor<float> output;
+        auto output = process_vae_temporal_tiles(input, plan, [&](const sd::Tensor<float>& z_chunk, const VAETemporalTile& tile) {
-        for (int64_t start = 0; start < total_frames - plan.overlap; start += plan.stride) {
-            const int64_t end       = std::min<int64_t>(total_frames, start + plan.frames);
-            const int chunk_overlap = end < total_frames ? plan.overlap : 0;
-            auto z_chunk            = sd::ops::slice(input, 2, start, end);
-
             LOG_DEBUG("LTX VAE temporal tile %lld/%d: latent frames [%lld, %lld), overlap=%d",
-                      (long long)(start / plan.stride + 1),
+                      (long long)tile.index + 1,
-                      plan.num_tiles,
+                      (int)plan.tiles.size(),
-                      (long long)start,
+                      (long long)tile.start,
-                      (long long)end,
+                      (long long)tile.end,
-                      chunk_overlap);
+                      tile.overlap);
 
             auto get_graph = [&]() -> ggml_cgraph* {
                 return build_temporal_tile_graph(z_chunk,
-                                                 static_cast<int>(start),
+                                                 static_cast<int>(tile.start),
-                                                 chunk_overlap);
+                                                 tile.overlap);
             };
-            auto chunk = restore_trailing_singleton_dims(GGMLRunner::compute<float>(get_graph, n_threads, true, true, true),
+            return restore_trailing_singleton_dims(GGMLRunner::compute<float>(get_graph, n_threads, true, true, true),
                                                    expected_dim);
-            if (chunk.empty()) {
+        });
-                free_cache_ctx_and_buffer();
-                cache_tensor_map.clear();
-                return {};
-            }
-            output = output.empty() ? std::move(chunk) : sd::ops::concat(output, chunk, 2);
-        }
 
         free_cache_ctx_and_buffer();
         cache_tensor_map.clear();
         return output;
     }
 
+    sd::Tensor<float> _compute_temporal_tiled(const int n_threads,
+                                              const sd::Tensor<float>& input,
+                                              VAETemporalDirection direction,
+                                              const VAETemporalTilingConfig& config) override {
+        GGML_ASSERT(direction == VAETemporalDirection::DECODE);
+        return decode_temporal_tiled_streaming(n_threads,
+                                               input,
+                                               static_cast<size_t>(input.dim()),
+                                               config);
+    }
+
     ggml_cgraph* build_latent_statistics_graph(const sd::Tensor<float>& z_tensor, bool normalize) {
         ggml_cgraph* gf = new_graph_custom(1024);
         ggml_tensor* z  = make_input(z_tensor);
@@ -1446,9 +1404,6 @@ struct LTXVideoVAE : public VAE {
                 input = sd::ops::slice(input, 2, 0, cropped_t);
             }
         }
-        if (decode_graph && temporal_tiling_enabled && input.dim() == 5 && input.shape()[2] > 1) {
-            return decode_temporal_tiled_streaming(n_threads, input, expected_dim);
-        }
         auto get_graph = [&]() -> ggml_cgraph* {
             return build_graph(input, decode_graph);
         };

src/model/vae/minimax_h3_vae.hpp

@@ -559,6 +559,7 @@ namespace MiniMaxH3VAE {
 
         static sd_tiling_params_t h3_tiling(sd_tiling_params_t params) {
             params.enabled         = true;
+            params.temporal_tiling = false;
             params.tile_size_x     = 16;
             params.tile_size_y     = 16;
             params.target_overlap  = 0.25f;
@@ -624,16 +625,14 @@ namespace MiniMaxH3VAE {
             if (pad > 0) {
                 input = repeat_last_frame(input, pad);
             }
-            sd::Tensor<float> result;
+            auto plan   = make_vae_temporal_tile_plan(input.shape()[2], {17, 0});
-            for (int64_t start = 0; start < input.shape()[2]; start += 17) {
+            auto result = process_vae_temporal_tiles(input, plan, [&](const sd::Tensor<float>& chunk, const VAETemporalTile& tile) {
-                auto chunk   = sd::ops::slice(input, 2, start, start + 17);
+                SD_UNUSED(tile);
-                auto encoded = VAE::encode(n_threads, chunk, tiling, circular_x, circular_y);
+                return VAE::encode(n_threads, chunk, tiling, circular_x, circular_y);
-                if (encoded.empty()) {
+            });
+            if (result.empty()) {
                 return {};
             }
-                result = result.empty() ? std::move(encoded)
-                                        : sd::ops::concat(result, encoded, 2);
-            }
             if (result.shape()[2] > 3) {
                 result = sd::ops::slice(result, 2, 0, result.shape()[2] - 3);
             }
@@ -685,13 +684,12 @@ namespace MiniMaxH3VAE {
                 input = repeat_last_frame(input, pad_tokens);
             }
 
-            sd::Tensor<float> result;
             sd::Tensor<float> overlap;
-            for (int64_t i = 0; i < num_chunks; ++i) {
+            auto plan = make_vae_temporal_tile_plan(
-                int64_t start = i * tokens_per_chunk;
+                input.shape()[2],
-                int64_t end   = std::min(start + tokens_per_chunk + token_overlap,
+                {static_cast<int>(tokens_per_chunk + token_overlap), static_cast<int>(token_overlap)});
-                                         input.shape()[2]);
+            GGML_ASSERT(plan.tiles.size() == static_cast<size_t>(num_chunks));
-                auto chunk    = sd::ops::slice(input, 2, start, end);
+            auto result = process_vae_temporal_tiles(input, plan, [&](const sd::Tensor<float>& chunk, const VAETemporalTile& tile) {
                 auto decoded = VAE::decode(n_threads,
                                            chunk,
                                            tiling,
@@ -700,7 +698,7 @@ namespace MiniMaxH3VAE {
                                            circular_y,
                                            silent);
                 if (decoded.empty()) {
-                    return {};
+                    return sd::Tensor<float>();
                 }
 
                 int64_t first_end = std::min<int64_t>(frames_per_chunk, decoded.shape()[2]);
@@ -712,8 +710,6 @@ namespace MiniMaxH3VAE {
                     first   = blend_temporal(overlap, first, frame_overlap);
                     overlap = {};
                 }
-                result = result.empty() ? std::move(first)
-                                        : sd::ops::concat(result, first, 2);
 
                 if (decoded.shape()[2] > frames_per_chunk + frame_pre_padding) {
                     overlap = sd::ops::slice(decoded,
@@ -721,10 +717,14 @@ namespace MiniMaxH3VAE {
                                              frames_per_chunk + frame_pre_padding,
                                              decoded.shape()[2]);
                 }
-                if (i == num_chunks - 1 && !overlap.empty()) {
+                if (tile.last && !overlap.empty()) {
-                    result  = sd::ops::concat(result, overlap, 2);
+                    first   = sd::ops::concat(first, overlap, 2);
                     overlap = {};
                 }
+                return first;
+            });
+            if (result.empty()) {
+                return {};
             }
 
             int64_t expected_frames = input.shape()[2] <= 1 ? 1 : ((x.shape()[2] - 2) / 5) * 17 + 5;

src/model/vae/tae.hpp

@@ -819,6 +819,21 @@ struct TinyVideoAutoEncoder : public VAE {
         return "taehv";
     }
 
+    bool supports_temporal_tiling(VAETemporalDirection direction) const override {
+        return direction == VAETemporalDirection::DECODE && !sd_version_is_minimax_h3(version);
+    }
+
+    int get_temporal_tile_output_scale(VAETemporalDirection direction) const override {
+        SD_UNUSED(direction);
+        int scale = 1;
+        for (bool upscale : taehv.time_upscale) {
+            if (upscale) {
+                scale *= 2;
+            }
+        }
+        return scale;
+    }
+
     void get_param_tensors(std::map<std::string, ggml_tensor*>& tensors) override {
         taehv.get_param_tensors(tensors, weight_prefix);
     }

src/model/vae/vae.hpp

@@ -3,6 +3,7 @@
 
 #include "core/tensor_ggml.hpp"
 #include "model/common/block.hpp"
+#include "model/vae/vae_tiling.hpp"
 #include "model_manager.h"
 
 struct VAE : public GGMLRunner {
@@ -14,6 +15,87 @@ protected:
                                        const sd::Tensor<float>& z,
                                        bool decode_graph) = 0;
 
+    virtual bool supports_temporal_tiling(VAETemporalDirection direction) const {
+        SD_UNUSED(direction);
+        return false;
+    }
+
+    virtual int get_default_temporal_tile_frames(VAETemporalDirection direction) const {
+        SD_UNUSED(direction);
+        return 4;
+    }
+
+    virtual int get_default_temporal_tile_overlap(VAETemporalDirection direction) const {
+        SD_UNUSED(direction);
+        return 1;
+    }
+
+    virtual int get_temporal_tile_output_scale(VAETemporalDirection direction) const {
+        SD_UNUSED(direction);
+        return 1;
+    }
+
+    virtual sd::Tensor<float> _compute_temporal_tiled(const int n_threads,
+                                                      const sd::Tensor<float>& input,
+                                                      VAETemporalDirection direction,
+                                                      const VAETemporalTilingConfig& config) {
+        if (direction != VAETemporalDirection::DECODE) {
+            return _compute(n_threads, input, false);
+        }
+
+        VAETemporalTilingConfig resolved_config = config;
+        const int output_scale                  = get_temporal_tile_output_scale(direction);
+        if (output_scale > 1 &&
+            resolved_config.overlap == 0 &&
+            input.shape()[2] > resolved_config.tile_frames) {
+            LOG_WARN("%s temporal decode requires at least one overlapping latent frame; using overlap=1",
+                     get_desc().c_str());
+            resolved_config.overlap = 1;
+        }
+
+        auto plan = make_vae_temporal_tile_plan(input.shape()[2], resolved_config);
+        LOG_DEBUG("%s temporal tiling: tile_frames=%d, overlap=%d, total_frames=%lld, tiles=%d",
+                  get_desc().c_str(),
+                  plan.tile_frames,
+                  plan.overlap,
+                  (long long)input.shape()[2],
+                  (int)plan.tiles.size());
+        return process_vae_temporal_tiles_blended(
+            input,
+            plan,
+            output_scale,
+            [&](const sd::Tensor<float>& input_tile, const VAETemporalTile& tile) {
+                LOG_DEBUG("%s temporal tile %d/%d: input frames [%lld, %lld)",
+                          get_desc().c_str(),
+                          tile.index + 1,
+                          (int)plan.tiles.size(),
+                          (long long)tile.start,
+                          (long long)tile.end);
+                return _compute(n_threads, input_tile, true);
+            });
+    }
+
+    sd::Tensor<float> compute_with_temporal_tiling(const int n_threads,
+                                                   const sd::Tensor<float>& input,
+                                                   VAETemporalDirection direction,
+                                                   const sd_tiling_params_t& tiling_params) {
+        if (!tiling_params.temporal_tiling || input.dim() != 5 || input.shape()[2] <= 1) {
+            return _compute(n_threads, input, direction == VAETemporalDirection::DECODE);
+        }
+        if (!supports_temporal_tiling(direction)) {
+            LOG_WARN("%s does not support temporal tiling for %s; processing the full temporal dimension",
+                     get_desc().c_str(),
+                     direction == VAETemporalDirection::DECODE ? "decode" : "encode");
+            return _compute(n_threads, input, direction == VAETemporalDirection::DECODE);
+        }
+
+        auto config = resolve_vae_temporal_tiling_config(
+            tiling_params,
+            get_default_temporal_tile_frames(direction),
+            get_default_temporal_tile_overlap(direction));
+        return _compute_temporal_tiled(n_threads, input, direction, config);
+    }
+
     static inline void scale_tensor_to_minus1_1(sd::Tensor<float>* tensor) {
         GGML_ASSERT(tensor != nullptr);
         for (int64_t i = 0; i < tensor->numel(); ++i) {
@@ -40,10 +122,15 @@ protected:
                                     bool circular_x,
                                     bool circular_y,
                                     bool decode_graph,
+                                    const sd_tiling_params_t& tiling_params,
                                     const char* error_message,
                                     bool silent = false) {
         auto on_processing = [&](const sd::Tensor<float>& input_tile) {
-            auto output_tile = _compute(n_threads, input_tile, decode_graph);
+            auto output_tile = compute_with_temporal_tiling(
+                n_threads,
+                input_tile,
+                decode_graph ? VAETemporalDirection::DECODE : VAETemporalDirection::ENCODE,
+                tiling_params);
             if (output_tile.empty()) {
                 LOG_ERROR("%s", error_message);
                 return sd::Tensor<float>();
@@ -86,6 +173,10 @@ public:
 
     virtual int get_encoder_output_channels(int input_channels) = 0;
 
+    bool can_temporal_tile_decode() const {
+        return supports_temporal_tiling(VAETemporalDirection::DECODE);
+    }
+
     void get_tile_sizes(int& tile_size_x,
                         int& tile_size_y,
                         float& tile_overlap,
@@ -151,9 +242,13 @@ public:
                                    circular_x,
                                    circular_y,
                                    false,
+                                   tiling_params,
                                    "vae encode compute failed while processing a tile");
         } else {
-            output = _compute(n_threads, input, false);
+            output = compute_with_temporal_tiling(n_threads,
+                                                  input,
+                                                  VAETemporalDirection::ENCODE,
+                                                  tiling_params);
         }
 
         runner_done();
@@ -177,7 +272,6 @@ public:
         int64_t t0              = ggml_time_ms();
         sd::Tensor<float> input = x;
         sd::Tensor<float> output;
-        set_tiling_params(tiling_params);
 
         if (tiling_params.enabled) {
             const int scale_factor = get_scale_factor();
@@ -201,10 +295,14 @@ public:
                 circular_x,
                 circular_y,
                 true,
+                tiling_params,
                 "vae decode compute failed while processing a tile",
                 silent);
         } else {
-            output = _compute(n_threads, input, true);
+            output = compute_with_temporal_tiling(n_threads,
+                                                  input,
+                                                  VAETemporalDirection::DECODE,
+                                                  tiling_params);
         }
 
         runner_done();
@@ -226,10 +324,6 @@ public:
     virtual sd::Tensor<float> vae_to_diffusion_latents(const sd::Tensor<float>& latents)                           = 0;
     virtual void get_param_tensors(std::map<std::string, ggml_tensor*>& tensors)                                   = 0;
     virtual void set_conv2d_scale(float scale) { SD_UNUSED(scale); };
-    virtual void set_temporal_tiling_enabled(bool enabled) { SD_UNUSED(enabled); };
-    virtual void set_tiling_params(const sd_tiling_params_t& params) {
-        set_temporal_tiling_enabled(params.temporal_tiling);
-    };
 };
 
 struct FakeVAE : public VAE {

src/model/vae/vae_tiling.hpp

@@ -0,0 +1,213 @@
+#ifndef __SD_MODEL_VAE_VAE_TILING_HPP__
+#define __SD_MODEL_VAE_VAE_TILING_HPP__
+
+#include <algorithm>
+#include <cstdint>
+#include <utility>
+#include <vector>
+
+#include "core/tensor.hpp"
+#include "core/util.h"
+
+enum class VAETemporalDirection {
+    ENCODE,
+    DECODE,
+};
+
+struct VAETemporalTilingConfig {
+    int tile_frames = 1;
+    int overlap     = 0;
+};
+
+struct VAETemporalTile {
+    int index     = 0;
+    int64_t start = 0;
+    int64_t end   = 0;
+    int overlap   = 0;
+    bool first    = false;
+    bool last     = false;
+};
+
+struct VAETemporalTilePlan {
+    int tile_frames = 1;
+    int overlap     = 0;
+    int stride      = 1;
+    std::vector<VAETemporalTile> tiles;
+};
+
+inline VAETemporalTilingConfig resolve_vae_temporal_tiling_config(const sd_tiling_params_t& params,
+                                                                  int default_tile_frames,
+                                                                  int default_overlap) {
+    VAETemporalTilingConfig config;
+    config.tile_frames = std::max(1, default_tile_frames);
+    config.overlap     = std::max(0, default_overlap);
+
+    for (const auto& [key, value] : parse_key_value_args(params.extra_tiling_args, "VAE extra tiling arg")) {
+        if (key != "temporal_tile_frames" && key != "temporal_tile_size" && key != "temporal_tile_overlap") {
+            continue;
+        }
+
+        int parsed = 0;
+        if (!parse_strict_int(value, parsed)) {
+            LOG_WARN("ignoring invalid VAE extra tiling arg '%s=%s'", key.c_str(), value.c_str());
+        } else if (key == "temporal_tile_overlap") {
+            config.overlap = std::max(0, parsed);
+        } else {
+            config.tile_frames = std::max(1, parsed);
+        }
+    }
+    return config;
+}
+
+inline VAETemporalTilePlan make_vae_temporal_tile_plan(int64_t total_frames,
+                                                       const VAETemporalTilingConfig& config) {
+    VAETemporalTilePlan plan;
+    plan.tile_frames = std::max(1, config.tile_frames);
+    plan.overlap     = std::max(0, config.overlap);
+    if (total_frames <= 1) {
+        plan.overlap = 0;
+    }
+
+    if (plan.overlap >= plan.tile_frames) {
+        LOG_WARN("temporal_tile_overlap (%d) is greater than or equal to temporal_tile_frames (%d), adjusting values to avoid empty decode windows",
+                 plan.overlap,
+                 plan.tile_frames);
+        plan.overlap = plan.tile_frames - 1;
+    }
+    if (total_frames > 1 && plan.overlap >= total_frames) {
+        LOG_WARN("temporal_tile_overlap (%d) is greater than or equal to total frames (%lld), adjusting values to process at least one tile",
+                 plan.overlap,
+                 (long long)total_frames);
+        plan.overlap = static_cast<int>(total_frames - 1);
+    }
+
+    plan.stride = std::max(1, plan.tile_frames - plan.overlap);
+    for (int64_t start = 0; start < total_frames - plan.overlap; start += plan.stride) {
+        VAETemporalTile tile;
+        tile.index   = static_cast<int>(plan.tiles.size());
+        tile.start   = start;
+        tile.end     = std::min<int64_t>(total_frames, start + plan.tile_frames);
+        tile.overlap = tile.end < total_frames ? plan.overlap : 0;
+        tile.first   = start == 0;
+        tile.last    = tile.end == total_frames;
+        plan.tiles.push_back(tile);
+    }
+    return plan;
+}
+
+template <typename Fn>
+inline sd::Tensor<float> process_vae_temporal_tiles(const sd::Tensor<float>& input,
+                                                    const VAETemporalTilePlan& plan,
+                                                    Fn&& on_processing) {
+    sd::Tensor<float> output;
+    for (const auto& tile : plan.tiles) {
+        auto input_tile  = sd::ops::slice(input, 2, tile.start, tile.end);
+        auto output_tile = on_processing(input_tile, tile);
+        if (output_tile.empty()) {
+            return {};
+        }
+        output = output.empty() ? std::move(output_tile)
+                                : sd::ops::concat(output, output_tile, 2);
+    }
+    return output;
+}
+
+template <typename Fn>
+inline sd::Tensor<float> process_vae_temporal_tiles_blended(const sd::Tensor<float>& input,
+                                                            const VAETemporalTilePlan& plan,
+                                                            int output_scale,
+                                                            Fn&& on_processing) {
+    GGML_ASSERT(output_scale >= 1);
+    const int64_t output_frames = 1 + (input.shape()[2] - 1) * output_scale;
+    const int overlap_frames    = plan.overlap > 0 ? 1 + (plan.overlap - 1) * output_scale : 0;
+    std::vector<float> weights(static_cast<size_t>(output_frames), 0.f);
+    sd::Tensor<float> output;
+
+    auto smootherstep = [](float value) {
+        return value * value * value * (value * (value * 6.f - 15.f) + 10.f);
+    };
+
+    for (const auto& tile : plan.tiles) {
+        auto input_tile  = sd::ops::slice(input, 2, tile.start, tile.end);
+        auto output_tile = on_processing(input_tile, tile);
+        if (output_tile.empty()) {
+            return {};
+        }
+
+        const int64_t expected_tile_frames = 1 + (input_tile.shape()[2] - 1) * output_scale;
+        if (output_tile.dim() < 3 || output_tile.shape()[2] != expected_tile_frames) {
+            LOG_ERROR("unexpected temporal tile output shape: expected %lld frames, got %lld",
+                      (long long)expected_tile_frames,
+                      output_tile.dim() < 3 ? -1LL : (long long)output_tile.shape()[2]);
+            return {};
+        }
+
+        if (output.empty()) {
+            auto output_shape = output_tile.shape();
+            output_shape[2]   = output_frames;
+            output            = sd::Tensor<float>::zeros(std::move(output_shape));
+        } else {
+            if (output.dim() != output_tile.dim()) {
+                LOG_ERROR("temporal tile output rank mismatch: expected %lld, got %lld",
+                          (long long)output.dim(),
+                          (long long)output_tile.dim());
+                return {};
+            }
+            for (size_t dim = 0; dim < static_cast<size_t>(output.dim()); ++dim) {
+                if (dim != 2 && output.shape()[dim] != output_tile.shape()[dim]) {
+                    LOG_ERROR("temporal tile output shape mismatch at dimension %zu", dim);
+                    return {};
+                }
+            }
+        }
+
+        const int64_t output_start = tile.start * output_scale;
+        const int64_t inner        = output.shape()[0] * output.shape()[1];
+        const int64_t outer        = output.numel() / (inner * output.shape()[2]);
+        const int64_t tile_frames  = output_tile.shape()[2];
+        for (int64_t frame = 0; frame < tile_frames; ++frame) {
+            float weight = 1.f;
+            if (!tile.first && overlap_frames > 0 && frame < overlap_frames) {
+                weight *= smootherstep(static_cast<float>(frame + 1) /
+                                       static_cast<float>(overlap_frames + 1));
+            }
+            if (!tile.last && overlap_frames > 0 && frame >= tile_frames - overlap_frames) {
+                weight *= smootherstep(static_cast<float>(tile_frames - frame) /
+                                       static_cast<float>(overlap_frames + 1));
+            }
+
+            const int64_t output_frame = output_start + frame;
+            GGML_ASSERT(output_frame >= 0 && output_frame < output_frames);
+            weights[static_cast<size_t>(output_frame)] += weight;
+            for (int64_t outer_index = 0; outer_index < outer; ++outer_index) {
+                const int64_t src_offset = (outer_index * tile_frames + frame) * inner;
+                const int64_t dst_offset = (outer_index * output_frames + output_frame) * inner;
+                for (int64_t inner_index = 0; inner_index < inner; ++inner_index) {
+                    output[dst_offset + inner_index] += output_tile[src_offset + inner_index] * weight;
+                }
+            }
+        }
+    }
+
+    if (output.empty()) {
+        return {};
+    }
+    const int64_t inner = output.shape()[0] * output.shape()[1];
+    const int64_t outer = output.numel() / (inner * output.shape()[2]);
+    for (int64_t frame = 0; frame < output_frames; ++frame) {
+        const float weight = weights[static_cast<size_t>(frame)];
+        if (weight <= 0.f) {
+            LOG_ERROR("temporal tiling left output frame %lld uncovered", (long long)frame);
+            return {};
+        }
+        for (int64_t outer_index = 0; outer_index < outer; ++outer_index) {
+            const int64_t offset = (outer_index * output_frames + frame) * inner;
+            for (int64_t inner_index = 0; inner_index < inner; ++inner_index) {
+                output[offset + inner_index] /= weight;
+            }
+        }
+    }
+    return output;
+}
+
+#endif  // __SD_MODEL_VAE_VAE_TILING_HPP__

src/model/vae/wan_vae.hpp

@@ -1219,9 +1219,9 @@ namespace WAN {
             return out;
         }
 
-        ggml_tensor* decode_partial(GGMLRunnerContext* ctx,
+        ggml_tensor* decode_tiled_chunk(GGMLRunnerContext* ctx,
                                         ggml_tensor* z,
-                                    int i,
+                                        int chunk_idx,
                                         int64_t b = 1) {
             // z: [b*c, t, h, w]
             GGML_ASSERT(b == 1);
@@ -1229,14 +1229,30 @@ namespace WAN {
             auto decoder = std::dynamic_pointer_cast<Decoder3d>(blocks["decoder"]);
             auto conv2   = std::dynamic_pointer_cast<CausalConv3d>(blocks["conv2"]);
 
-            auto x = conv2->forward(ctx, z);
+            ggml_tensor* x;
-            // sd::ggml_graph_cut::mark_graph_cut(x, "wan_vae.decode_partial.prelude", "x");
+            if (is_2D) {
-            auto in   = ggml_ext_slice(ctx->ggml_ctx, x, 2, i, i + 1);  // [b*c, 1, h, w]
+                auto conv2_2d = std::dynamic_pointer_cast<Conv2dBut3d>(blocks["conv2"]);
+                x             = conv2_2d->forward(ctx, z);
+            } else {
+                x = conv2->forward(ctx, z);
+            }
+
+            ggml_tensor* out = nullptr;
+            for (int64_t frame = 0; frame < x->ne[2]; ++frame) {
+                const int global_frame = chunk_idx + static_cast<int>(frame);
+                auto in                = ggml_ext_slice(ctx->ggml_ctx, x, 2, frame, frame + 1);
                 _conv_idx              = 0;
-            auto out  = decoder->forward(ctx, in, b, _feat_map, _conv_idx, i);
+                auto out_frame         = decoder->forward(ctx, in, b, _feat_map, _conv_idx, global_frame);
-            out       = unpatchify(ctx->ggml_ctx, out, patch_size, b);
+                if (is_2D && global_frame > 0) {
-            // sd::ggml_graph_cut::mark_graph_cut(out, "wan_vae.decode_partial.final", "out");
+                    auto repeated = out_frame;
-            return out;
+                    for (int repeat = 1; repeat < 4; ++repeat) {
+                        repeated = ggml_concat(ctx->ggml_ctx, repeated, out_frame, 2);
+                    }
+                    out_frame = repeated;
+                }
+                out = out == nullptr ? out_frame : ggml_concat(ctx->ggml_ctx, out, out_frame, 2);
+            }
+            return unpatchify(ctx->ggml_ctx, out, patch_size, b);
         }
     };
 
@@ -1272,6 +1288,15 @@ namespace WAN {
             return "wan_vae";
         }
 
+        bool supports_temporal_tiling(VAETemporalDirection direction) const override {
+            return direction == VAETemporalDirection::DECODE;
+        }
+
+        int get_temporal_tile_output_scale(VAETemporalDirection direction) const override {
+            SD_UNUSED(direction);
+            return 4;
+        }
+
         void get_param_tensors(std::map<std::string, ggml_tensor*>& tensors) override {
             ae.get_param_tensors(tensors, weight_prefix);
         }
@@ -1346,8 +1371,8 @@ namespace WAN {
             return gf;
         }
 
-        ggml_cgraph* build_graph_partial(const sd::Tensor<float>& z_tensor, bool decode_graph, int i) {
+        ggml_cgraph* build_temporal_tile_graph(const sd::Tensor<float>& z_tensor, int chunk_idx) {
-            ggml_cgraph* gf = new_graph_custom(20480);
+            ggml_cgraph* gf = new_graph_custom(std::max<size_t>(20480, 10240 * z_tensor.shape()[2]));
 
             ae.clear_cache();
 
@@ -1360,7 +1385,7 @@ namespace WAN {
 
             auto runner_ctx = get_context();
 
-            ggml_tensor* out = decode_graph ? ae.decode_partial(&runner_ctx, z, i) : ae.encode(&runner_ctx, z);
+            ggml_tensor* out = ae.decode_tiled_chunk(&runner_ctx, z, chunk_idx);
 
             for (size_t feat_idx = 0; feat_idx < ae._feat_map.size(); feat_idx++) {
                 ggml_tensor* feat_cache = ae._feat_map[feat_idx];
@@ -1375,20 +1400,53 @@ namespace WAN {
             return gf;
         }
 
+        sd::Tensor<float> _compute_temporal_tiled(const int n_threads,
+                                                  const sd::Tensor<float>& input,
+                                                  VAETemporalDirection direction,
+                                                  const VAETemporalTilingConfig& config) override {
+            GGML_ASSERT(direction == VAETemporalDirection::DECODE);
+            VAETemporalTilingConfig stateful_config = config;
+            stateful_config.overlap                 = 0;
+            auto plan                               = make_vae_temporal_tile_plan(input.shape()[2], stateful_config);
+
+            LOG_DEBUG("Wan VAE stateful temporal tiling: tile_frames=%d, total latent frames=%lld, tiles=%d",
+                      plan.tile_frames,
+                      (long long)input.shape()[2],
+                      (int)plan.tiles.size());
+
+            free_cache_ctx_and_buffer();
+            cache_tensor_map.clear();
+            ae.clear_cache();
+
+            auto output = process_vae_temporal_tiles(input, plan, [&](const sd::Tensor<float>& input_tile, const VAETemporalTile& tile) {
+                LOG_DEBUG("Wan VAE temporal tile %d/%d: latent frames [%lld, %lld)",
+                          tile.index + 1,
+                          (int)plan.tiles.size(),
+                          (long long)tile.start,
+                          (long long)tile.end);
+                auto get_graph = [&]() -> ggml_cgraph* {
+                    return build_temporal_tile_graph(input_tile, static_cast<int>(tile.start));
+                };
+                return restore_trailing_singleton_dims(
+                    GGMLRunner::compute<float>(get_graph, n_threads, true, true, true),
+                    static_cast<size_t>(input.dim()));
+            });
+
+            free_cache_ctx_and_buffer();
+            cache_tensor_map.clear();
+            ae.clear_cache();
+            return output;
+        }
+
         sd::Tensor<float> _compute(const int n_threads,
                                    const sd::Tensor<float>& z,
                                    bool decode_graph) override {
-            if (true) {
             sd::Tensor<float> input;
             if (z.dim() == 4) {
                 input = z.unsqueeze(2);
             }
             auto get_graph = [&]() -> ggml_cgraph* {
-                    if (input.empty()) {
+                return build_graph(input.empty() ? z : input, decode_graph);
-                        return build_graph(z, decode_graph);
-                    } else {
-                        return build_graph(input, decode_graph);
-                    }
             };
             auto result = restore_trailing_singleton_dims(GGMLRunner::compute<float>(get_graph, n_threads, true, true, true),
                                                           input.empty() ? z.dim() : input.dim());
@@ -1396,37 +1454,6 @@ namespace WAN {
                 result.squeeze_(2);
             }
             return result;
-            } else {  // chunk 1 result is weird
-                ae.clear_cache();
-                int64_t t      = z.shape()[2];
-                int i          = 0;
-                auto get_graph = [&]() -> ggml_cgraph* {
-                    return build_graph_partial(z, decode_graph, i);
-                };
-                auto out_opt = GGMLRunner::compute<float>(get_graph, n_threads, true, true, true);
-                if (!out_opt.has_value()) {
-                    return {};
-                }
-                sd::Tensor<float> out = std::move(*out_opt);
-                ae.clear_cache();
-                if (t == 1) {
-                    return out;
-                }
-
-                sd::Tensor<float> output = std::move(out);
-
-                for (i = 1; i < t; i++) {
-                    auto chunk_opt = GGMLRunner::compute<float>(get_graph, n_threads, true, true, true);
-                    if (!chunk_opt.has_value()) {
-                        return {};
-                    }
-                    out = std::move(*chunk_opt);
-                    ae.clear_cache();
-                    output = sd::ops::concat(output, out, 2);
-                }
-                free_cache_ctx_and_buffer();
-                return output;
-            }
         }
 
         void test() {

src/stable-diffusion.cpp

@@ -2378,11 +2378,9 @@ public:
             sd::Tensor<float> vae_latents;
             sd::Tensor<float> decoded;
             if (preview_vae) {
-                preview_vae->set_temporal_tiling_enabled(vae_tiling_params.temporal_tiling);
                 vae_latents = preview_vae->diffusion_to_vae_latents(_latents);
                 decoded     = preview_vae->decode(n_threads, vae_latents, vae_tiling_params, is_video, circular_x, circular_y, true);
             } else {
-                first_stage_model->set_temporal_tiling_enabled(vae_tiling_params.temporal_tiling);
                 vae_latents = first_stage_model->diffusion_to_vae_latents(_latents);
                 decoded     = first_stage_model->decode(n_threads, vae_latents, vae_tiling_params, is_video, circular_x, circular_y, true);
             }
@@ -3085,16 +3083,14 @@ public:
             return sd::ops::clamp((x + 1.f) * 0.5f, 0.0f, 1.0f);
         }
         auto latents                      = first_stage_model->diffusion_to_vae_latents(x);
-        first_stage_model->set_temporal_tiling_enabled(vae_tiling_params.temporal_tiling);
         auto decoded                      = first_stage_model->decode(n_threads, latents, vae_tiling_params, decode_video, circular_x, circular_y);
-        if (decoded.empty() && auto_fit_enabled) {
+        const bool prefer_temporal_tiling = decode_video && first_stage_model->can_temporal_tile_decode();
-            bool prefer_temporal_tiling = decode_video && std::dynamic_pointer_cast<LTXVideoVAE>(first_stage_model) != nullptr;
+        while (decoded.empty() &&
-            if (sd::backend_fit::prepare_vae_decode_retry_tiling(vae_tiling_params, prefer_temporal_tiling)) {
+               auto_fit_enabled &&
+               sd::backend_fit::prepare_vae_decode_retry_tiling(vae_tiling_params, prefer_temporal_tiling)) {
             first_stage_model->free_compute_buffer();
-                first_stage_model->set_temporal_tiling_enabled(vae_tiling_params.temporal_tiling);
             decoded = first_stage_model->decode(n_threads, latents, vae_tiling_params, decode_video, circular_x, circular_y);
         }
-        }
         return decoded;
     }