lavfi: add Vulkan filtering framework

This commit adds a Vulkan filtering infrastructure for libavfilter.
It attempts to abstract as much as possible of the Vulkan API from filters.

The way the hwcontext and the framework are designed permits for parallel,
non-CPU-blocking filtering throughout, with the exception of up/downloading
and mapping.

1 files changed, 323 insertions, 0 deletions

diff --git a/libavfilter/vulkan.h b/libavfilter/vulkan.h
new file mode 100644
index 0000000000..744e8c32f7
--- /dev/null
+++ b/libavfilter/vulkan.h
@@ -0,0 +1,323 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVFILTER_VULKAN_H
+#define AVFILTER_VULKAN_H
+
+#include "avfilter.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/bprint.h"
+#include "libavutil/hwcontext.h"
+#include "libavutil/hwcontext_vulkan.h"
+
+/* GLSL management macros */
+#define INDENT(N) INDENT_##N
+#define INDENT_0
+#define INDENT_1 INDENT_0 "    "
+#define INDENT_2 INDENT_1 INDENT_1
+#define INDENT_3 INDENT_2 INDENT_1
+#define INDENT_4 INDENT_3 INDENT_1
+#define INDENT_5 INDENT_4 INDENT_1
+#define INDENT_6 INDENT_5 INDENT_1
+#define C(N, S)          INDENT(N) #S "\n"
+#define GLSLC(N, S)      av_bprintf(&shd->src, C(N, S))
+#define GLSLA(...)       av_bprintf(&shd->src, __VA_ARGS__)
+#define GLSLF(N, S, ...) av_bprintf(&shd->src, C(N, S), __VA_ARGS__)
+#define GLSLD(D)         GLSLC(0, );                                           \
+                         av_bprint_append_data(&shd->src, D, strlen(D));       \
+                         GLSLC(0, )
+
+/* Helper, pretty much every Vulkan return value needs to be checked */
+#define RET(x)                                                                 \
+    do {                                                                       \
+        if ((err = (x)) < 0)                                                   \
+            goto fail;                                                         \
+    } while (0)
+
+/* Useful for attaching immutable samplers to arrays */
+#define DUP_SAMPLER_ARRAY4(x) (VkSampler []){ x, x, x, x, }
+
+typedef struct SPIRVShader {
+    const char *name;                       /* Name for id/debugging purposes */
+    AVBPrint src;
+    int local_size[3];                      /* Compute shader workgroup sizes */
+    VkPipelineShaderStageCreateInfo shader;
+} SPIRVShader;
+
+typedef struct VulkanDescriptorSetBinding {
+    const char         *name;
+    VkDescriptorType    type;
+    const char         *mem_layout;  /* Storage images (rgba8, etc.) and buffers (std430, etc.) */
+    const char         *mem_quali;   /* readonly, writeonly, etc. */
+    const char         *buf_content; /* For buffers */
+    uint32_t            dimensions;  /* Needed for e.g. sampler%iD */
+    uint32_t            elems;       /* 0 - scalar, 1 or more - vector */
+    VkShaderStageFlags  stages;
+    const VkSampler    *samplers;    /* Immutable samplers, length - #elems */
+    void               *updater;     /* Pointer to VkDescriptor*Info */
+} VulkanDescriptorSetBinding;
+
+typedef struct FFVkBuffer {
+    VkBuffer buf;
+    VkDeviceMemory mem;
+    VkMemoryPropertyFlagBits flags;
+} FFVkBuffer;
+
+typedef struct VulkanPipeline {
+    VkPipelineBindPoint bind_point;
+
+    /* Contexts */
+    VkPipelineLayout pipeline_layout;
+    VkPipeline       pipeline;
+
+    /* Shaders */
+    SPIRVShader **shaders;
+    int shaders_num;
+
+    /* Push consts */
+    VkPushConstantRange *push_consts;
+    int push_consts_num;
+
+    /* Descriptors */
+    VkDescriptorSetLayout      *desc_layout;
+    VkDescriptorPool            desc_pool;
+    VkDescriptorSet            *desc_set;
+    VkDescriptorUpdateTemplate *desc_template;
+    int                         descriptor_sets_num;
+    int                         pool_size_desc_num;
+
+    /* Temporary, used to store data in between initialization stages */
+    VkDescriptorUpdateTemplateCreateInfo *desc_template_info;
+    VkDescriptorPoolSize *pool_size_desc;
+} VulkanPipeline;
+
+typedef struct FFVkExecContext {
+    VkCommandPool pool;
+    VkCommandBuffer buf;
+    VkQueue queue;
+    VkFence fence;
+
+    VulkanPipeline *bound_pl;
+
+    VkSemaphore *sem_wait;
+    int sem_wait_alloc; /* Allocated sem_wait */
+    int sem_wait_cnt;
+
+    VkPipelineStageFlagBits *sem_wait_dst;
+    int sem_wait_dst_alloc; /* Allocated sem_wait_dst */
+
+    VkSemaphore *sem_sig;
+    int sem_sig_alloc; /* Allocated sem_sig */
+    int sem_sig_cnt;
+} FFVkExecContext;
+
+typedef struct VulkanFilterContext {
+    const AVClass         *class;
+
+    AVBufferRef           *device_ref;
+    AVBufferRef           *frames_ref; /* For in-place filtering */
+    AVHWDeviceContext     *device;
+    AVVulkanDeviceContext *hwctx;
+
+    /* Properties */
+    int                 output_width;
+    int                output_height;
+    enum AVPixelFormat output_format;
+    enum AVPixelFormat  input_format;
+
+    /* Samplers */
+    VkSampler **samplers;
+    int samplers_num;
+
+    /* Exec contexts */
+    FFVkExecContext **exec_ctx;
+    int exec_ctx_num;
+
+    /* Pipelines (each can have 1 shader of each type) */
+    VulkanPipeline **pipelines;
+    int pipelines_num;
+
+    void *scratch; /* Scratch memory used only in functions */
+    unsigned int scratch_size;
+} VulkanFilterContext;
+
+/* Identity mapping - r = r, b = b, g = g, a = a */
+extern const VkComponentMapping ff_comp_identity_map;
+
+/**
+ * General lavfi IO functions
+ */
+int  ff_vk_filter_query_formats        (AVFilterContext *avctx);
+int  ff_vk_filter_init                 (AVFilterContext *avctx);
+int  ff_vk_filter_config_input         (AVFilterLink   *inlink);
+int  ff_vk_filter_config_output        (AVFilterLink  *outlink);
+int  ff_vk_filter_config_output_inplace(AVFilterLink  *outlink);
+void ff_vk_filter_uninit               (AVFilterContext *avctx);
+
+/**
+ * Converts Vulkan return values to strings
+ */
+const char *ff_vk_ret2str(VkResult res);
+
+/**
+ * Gets the glsl format string for a pixel format
+ */
+const char *ff_vk_shader_rep_fmt(enum AVPixelFormat pixfmt);
+
+/**
+ * Create a Vulkan sampler, will be auto-freed in ff_vk_filter_uninit()
+ */
+VkSampler *ff_vk_init_sampler(AVFilterContext *avctx, int unnorm_coords,
+                              VkFilter filt);
+
+/**
+ * Create an imageview.
+ */
+int ff_vk_create_imageview(AVFilterContext *avctx, VkImageView *v, VkImage img,
+                           VkFormat fmt, const VkComponentMapping map);
+
+/**
+ * Destroy an imageview. Command buffer must have completed executing, which
+ * ff_vk_submit_exec_queue() will ensure
+ */
+void ff_vk_destroy_imageview(AVFilterContext *avctx, VkImageView *v);
+
+/**
+ * Define a push constant for a given stage into a pipeline.
+ * Must be called before the pipeline layout has been initialized.
+ */
+int ff_vk_add_push_constant(AVFilterContext *avctx, VulkanPipeline *pl,
+                            int offset, int size, VkShaderStageFlagBits stage);
+
+/**
+ * Inits a pipeline. Everything in it will be auto-freed when calling
+ * ff_vk_filter_uninit().
+ */
+VulkanPipeline *ff_vk_create_pipeline(AVFilterContext *avctx);
+
+/**
+ * Inits a shader for a specific pipeline. Will be auto-freed on uninit.
+ */
+SPIRVShader *ff_vk_init_shader(AVFilterContext *avctx, VulkanPipeline *pl,
+                               const char *name, VkShaderStageFlags stage);
+
+/**
+ * Writes the workgroup size for a shader.
+ */
+void ff_vk_set_compute_shader_sizes(AVFilterContext *avctx, SPIRVShader *shd,
+                                    int local_size[3]);
+
+/**
+ * Adds a descriptor set to the shader and registers them in the pipeline.
+ */
+int ff_vk_add_descriptor_set(AVFilterContext *avctx, VulkanPipeline *pl,
+                             SPIRVShader *shd, VulkanDescriptorSetBinding *desc,
+                             int num, int only_print_to_shader);
+
+/**
+ * Compiles the shader, entrypoint must be set to "main".
+ */
+int ff_vk_compile_shader(AVFilterContext *avctx, SPIRVShader *shd,
+                         const char *entrypoint);
+
+/**
+ * Initializes the pipeline layout after all shaders and descriptor sets have
+ * been finished.
+ */
+int ff_vk_init_pipeline_layout(AVFilterContext *avctx, VulkanPipeline *pl);
+
+/**
+ * Initializes a compute pipeline. Will pick the first shader with the
+ * COMPUTE flag set.
+ */
+int ff_vk_init_compute_pipeline(AVFilterContext *avctx, VulkanPipeline *pl);
+
+/**
+ * Updates a descriptor set via the updaters defined.
+ * Can be called immediately after pipeline creation, but must be called
+ * at least once before queue submission.
+ */
+void ff_vk_update_descriptor_set(AVFilterContext *avctx, VulkanPipeline *pl,
+                                 int set_id);
+
+/**
+ * Init an execution context for command recording and queue submission.
+ * WIll be auto-freed on uninit.
+ */
+int ff_vk_create_exec_ctx(AVFilterContext *avctx, FFVkExecContext **ctx, int queue);
+
+/**
+ * Begin recording to the command buffer. Previous execution must have been
+ * completed, which ff_vk_submit_exec_queue() will ensure.
+ */
+int ff_vk_start_exec_recording(AVFilterContext *avctx, FFVkExecContext *e);
+
+/**
+ * Add a command to bind the completed pipeline and its descriptor sets.
+ * Must be called after ff_vk_start_exec_recording() and before submission.
+ */
+void ff_vk_bind_pipeline_exec(AVFilterContext *avctx, FFVkExecContext *e,
+                              VulkanPipeline *pl);
+
+/**
+ * Updates push constants.
+ * Must be called after binding a pipeline if any push constants were defined.
+ */
+void ff_vk_update_push_exec(AVFilterContext *avctx, FFVkExecContext *e,
+                            VkShaderStageFlagBits stage, int offset,
+                            size_t size, void *src);
+
+/**
+ * Adds a frame as a queue dependency. This manages semaphore signalling.
+ * Must be called before submission.
+ */
+int ff_vk_add_exec_dep(AVFilterContext *avctx, FFVkExecContext *e,
+                       AVFrame *frame, VkPipelineStageFlagBits in_wait_dst_flag);
+
+/**
+ * Submits a command buffer to the queue for execution.
+ * Will block until execution has finished in order to simplify resource
+ * management.
+ */
+int ff_vk_submit_exec_queue(AVFilterContext *avctx, FFVkExecContext *e);
+
+/**
+ * Create a VkBuffer with the specified parameters.
+ */
+int ff_vk_create_buf(AVFilterContext *avctx, FFVkBuffer *buf, size_t size,
+                     VkBufferUsageFlags usage, VkMemoryPropertyFlagBits flags);
+
+/**
+ * Maps the buffer to userspace. Set invalidate to 1 if reading the contents
+ * is necessary.
+ */
+int ff_vk_map_buffers(AVFilterContext *avctx, FFVkBuffer *buf, uint8_t *mem[],
+                      int nb_buffers, int invalidate);
+
+/**
+ * Unmaps the buffer from userspace. Set flush to 1 to write and sync.
+ */
+int ff_vk_unmap_buffers(AVFilterContext *avctx, FFVkBuffer *buf, int nb_buffers,
+                        int flush);
+
+/**
+ * Frees a buffer.
+ */
+void ff_vk_free_buf(AVFilterContext *avctx, FFVkBuffer *buf);
+
+#endif /* AVFILTER_VULKAN_H */