/*

  * Copyright (C) 2012 Peng  Gao     <peng@multicorewareinc.com>
  * Copyright (C) 2012 Li    Cao     <li@multicorewareinc.com>
  * Copyright (C) 2012 Wei   Gao     <weigao@multicorewareinc.com>
  * Copyright (C) 2013 Lenny Wang    <lwanghpc@gmail.com>

  *
  * 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
  */
 
 #include "opencl.h"
 #include "avstring.h"
 #include "log.h"
 #include "avassert.h"

 #include "opt.h"

 
 #if HAVE_THREADS

 #include "thread.h"

 #include "atomic.h"

 static pthread_mutex_t * volatile atomic_opencl_lock = NULL;

 #define LOCK_OPENCL pthread_mutex_lock(atomic_opencl_lock)
 #define UNLOCK_OPENCL pthread_mutex_unlock(atomic_opencl_lock)
 #else

 #define LOCK_OPENCL
 #define UNLOCK_OPENCL
 #endif
 
 #define MAX_KERNEL_CODE_NUM 200
 
 typedef struct {
     int is_compiled;
     const char *kernel_string;
 } KernelCode;
 
 typedef struct {

     const AVClass *class;
     int log_offset;
     void *log_ctx;

     int init_count;

     int opt_init_flag;
      /**
      * if set to 1, the OpenCL environment was created by the user and
      * passed as AVOpenCLExternalEnv when initing ,0:created by opencl wrapper.
      */
     int is_user_created;

     int platform_idx;
     int device_idx;

     cl_platform_id platform_id;
     cl_device_type device_type;
     cl_context context;
     cl_device_id device_id;
     cl_command_queue command_queue;
     int kernel_code_count;
     KernelCode kernel_code[MAX_KERNEL_CODE_NUM];

     AVOpenCLDeviceList device_list;

 } OpenclContext;

 #define OFFSET(x) offsetof(OpenclContext, x)

 
 static const AVOption opencl_options[] = {
      { "platform_idx",        "set platform index value",  OFFSET(platform_idx),  AV_OPT_TYPE_INT,    {.i64=-1}, -1, INT_MAX},
      { "device_idx",          "set device index value",    OFFSET(device_idx),    AV_OPT_TYPE_INT,    {.i64=-1}, -1, INT_MAX},

      { NULL }

 };
 

 static const AVClass openclutils_class = {

     .class_name                = "opencl",

     .option                    = opencl_options,

     .item_name                 = av_default_item_name,
     .version                   = LIBAVUTIL_VERSION_INT,

     .log_level_offset_offset   = offsetof(OpenclContext, log_offset),
     .parent_log_context_offset = offsetof(OpenclContext, log_ctx),

 };
 

 static OpenclContext opencl_ctx = {&openclutils_class};

 static const cl_device_type device_type[] = {CL_DEVICE_TYPE_GPU, CL_DEVICE_TYPE_CPU};

 typedef struct {
     int err_code;
     const char *err_str;
 } OpenclErrorMsg;
 
 static const OpenclErrorMsg opencl_err_msg[] = {

     {CL_DEVICE_NOT_FOUND,                               "DEVICE NOT FOUND"},
     {CL_DEVICE_NOT_AVAILABLE,                           "DEVICE NOT AVAILABLE"},
     {CL_COMPILER_NOT_AVAILABLE,                         "COMPILER NOT AVAILABLE"},
     {CL_MEM_OBJECT_ALLOCATION_FAILURE,                  "MEM OBJECT ALLOCATION FAILURE"},
     {CL_OUT_OF_RESOURCES,                               "OUT OF RESOURCES"},
     {CL_OUT_OF_HOST_MEMORY,                             "OUT OF HOST MEMORY"},
     {CL_PROFILING_INFO_NOT_AVAILABLE,                   "PROFILING INFO NOT AVAILABLE"},
     {CL_MEM_COPY_OVERLAP,                               "MEM COPY OVERLAP"},
     {CL_IMAGE_FORMAT_MISMATCH,                          "IMAGE FORMAT MISMATCH"},
     {CL_IMAGE_FORMAT_NOT_SUPPORTED,                     "IMAGE FORMAT NOT_SUPPORTED"},
     {CL_BUILD_PROGRAM_FAILURE,                          "BUILD PROGRAM FAILURE"},
     {CL_MAP_FAILURE,                                    "MAP FAILURE"},
     {CL_MISALIGNED_SUB_BUFFER_OFFSET,                   "MISALIGNED SUB BUFFER OFFSET"},
     {CL_EXEC_STATUS_ERROR_FOR_EVENTS_IN_WAIT_LIST,      "EXEC STATUS ERROR FOR EVENTS IN WAIT LIST"},
     {CL_COMPILE_PROGRAM_FAILURE,                        "COMPILE PROGRAM FAILURE"},
     {CL_LINKER_NOT_AVAILABLE,                           "LINKER NOT AVAILABLE"},
     {CL_LINK_PROGRAM_FAILURE,                           "LINK PROGRAM FAILURE"},
     {CL_DEVICE_PARTITION_FAILED,                        "DEVICE PARTITION FAILED"},
     {CL_KERNEL_ARG_INFO_NOT_AVAILABLE,                  "KERNEL ARG INFO NOT AVAILABLE"},
     {CL_INVALID_VALUE,                                  "INVALID VALUE"},
     {CL_INVALID_DEVICE_TYPE,                            "INVALID DEVICE TYPE"},
     {CL_INVALID_PLATFORM,                               "INVALID PLATFORM"},
     {CL_INVALID_DEVICE,                                 "INVALID DEVICE"},
     {CL_INVALID_CONTEXT,                                "INVALID CONTEXT"},
     {CL_INVALID_QUEUE_PROPERTIES,                       "INVALID QUEUE PROPERTIES"},
     {CL_INVALID_COMMAND_QUEUE,                          "INVALID COMMAND QUEUE"},
     {CL_INVALID_HOST_PTR,                               "INVALID HOST PTR"},
     {CL_INVALID_MEM_OBJECT,                             "INVALID MEM OBJECT"},
     {CL_INVALID_IMAGE_FORMAT_DESCRIPTOR,                "INVALID IMAGE FORMAT DESCRIPTOR"},
     {CL_INVALID_IMAGE_SIZE,                             "INVALID IMAGE SIZE"},
     {CL_INVALID_SAMPLER,                                "INVALID SAMPLER"},
     {CL_INVALID_BINARY,                                 "INVALID BINARY"},
     {CL_INVALID_BUILD_OPTIONS,                          "INVALID BUILD OPTIONS"},
     {CL_INVALID_PROGRAM,                                "INVALID PROGRAM"},
     {CL_INVALID_PROGRAM_EXECUTABLE,                     "INVALID PROGRAM EXECUTABLE"},
     {CL_INVALID_KERNEL_NAME,                            "INVALID KERNEL NAME"},
     {CL_INVALID_KERNEL_DEFINITION,                      "INVALID KERNEL DEFINITION"},
     {CL_INVALID_KERNEL,                                 "INVALID KERNEL"},
     {CL_INVALID_ARG_INDEX,                              "INVALID ARG INDEX"},
     {CL_INVALID_ARG_VALUE,                              "INVALID ARG VALUE"},
     {CL_INVALID_ARG_SIZE,                               "INVALID ARG_SIZE"},
     {CL_INVALID_KERNEL_ARGS,                            "INVALID KERNEL ARGS"},
     {CL_INVALID_WORK_DIMENSION,                         "INVALID WORK DIMENSION"},
     {CL_INVALID_WORK_GROUP_SIZE,                        "INVALID WORK GROUP SIZE"},
     {CL_INVALID_WORK_ITEM_SIZE,                         "INVALID WORK ITEM SIZE"},
     {CL_INVALID_GLOBAL_OFFSET,                          "INVALID GLOBAL OFFSET"},
     {CL_INVALID_EVENT_WAIT_LIST,                        "INVALID EVENT WAIT LIST"},
     {CL_INVALID_EVENT,                                  "INVALID EVENT"},
     {CL_INVALID_OPERATION,                              "INVALID OPERATION"},
     {CL_INVALID_GL_OBJECT,                              "INVALID GL OBJECT"},
     {CL_INVALID_BUFFER_SIZE,                            "INVALID BUFFER SIZE"},
     {CL_INVALID_MIP_LEVEL,                              "INVALID MIP LEVEL"},
     {CL_INVALID_GLOBAL_WORK_SIZE,                       "INVALID GLOBAL WORK SIZE"},
     {CL_INVALID_PROPERTY,                               "INVALID PROPERTY"},
     {CL_INVALID_IMAGE_DESCRIPTOR,                       "INVALID IMAGE DESCRIPTOR"},
     {CL_INVALID_COMPILER_OPTIONS,                       "INVALID COMPILER OPTIONS"},
     {CL_INVALID_LINKER_OPTIONS,                         "INVALID LINKER OPTIONS"},
     {CL_INVALID_DEVICE_PARTITION_COUNT,                 "INVALID DEVICE PARTITION COUNT"},

 };
 

 const char *av_opencl_errstr(cl_int status)

 {
     int i;

     for (i = 0; i < FF_ARRAY_ELEMS(opencl_err_msg); i++) {

         if (opencl_err_msg[i].err_code == status)
             return opencl_err_msg[i].err_str;
     }
     return "unknown error";
 }
 

 static void free_device_list(AVOpenCLDeviceList *device_list)
 {
     int i, j;
     if (!device_list)
         return;
     for (i = 0; i < device_list->platform_num; i++) {
         if (!device_list->platform_node[i])
             continue;
         for (j = 0; j < device_list->platform_node[i]->device_num; j++) {

             av_freep(&(device_list->platform_node[i]->device_node[j]->device_name));

             av_freep(&(device_list->platform_node[i]->device_node[j]));
         }
         av_freep(&device_list->platform_node[i]->device_node);

         av_freep(&(device_list->platform_node[i]->platform_name));

         av_freep(&device_list->platform_node[i]);
     }
     av_freep(&device_list->platform_node);
     device_list->platform_num = 0;
 }
 
 static int get_device_list(AVOpenCLDeviceList *device_list)
 {
     cl_int status;

     int i, j, k, device_num, total_devices_num, ret = 0;

     int *devices_num;
     cl_platform_id *platform_ids = NULL;
     cl_device_id *device_ids = NULL;
     AVOpenCLDeviceNode *device_node = NULL;

     size_t platform_name_size = 0;
     size_t device_name_size = 0;

     status = clGetPlatformIDs(0, NULL, &device_list->platform_num);
     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not get OpenCL platform ids: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }

     platform_ids = av_mallocz_array(device_list->platform_num, sizeof(cl_platform_id));

     if (!platform_ids)
         return AVERROR(ENOMEM);
     status = clGetPlatformIDs(device_list->platform_num, platform_ids, NULL);
     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                 "Could not get OpenCL platform ids: %s\n", av_opencl_errstr(status));

         ret = AVERROR_EXTERNAL;
         goto end;
     }

     device_list->platform_node = av_mallocz_array(device_list->platform_num, sizeof(AVOpenCLPlatformNode *));

     if (!device_list->platform_node) {
         ret = AVERROR(ENOMEM);
         goto end;
     }
     devices_num = av_mallocz(sizeof(int) * FF_ARRAY_ELEMS(device_type));
     if (!devices_num) {
         ret = AVERROR(ENOMEM);
         goto end;
     }
     for (i = 0; i < device_list->platform_num; i++) {
         device_list->platform_node[i] = av_mallocz(sizeof(AVOpenCLPlatformNode));
         if (!device_list->platform_node[i]) {
             ret = AVERROR(ENOMEM);
             goto end;
         }
         device_list->platform_node[i]->platform_id = platform_ids[i];
         status = clGetPlatformInfo(platform_ids[i], CL_PLATFORM_VENDOR,

                                    0, NULL, &platform_name_size);
         if (status != CL_SUCCESS) {
             av_log(&opencl_ctx, AV_LOG_WARNING,
                     "Could not get size of platform name: %s\n", av_opencl_errstr(status));
         } else {
             device_list->platform_node[i]->platform_name = av_malloc(platform_name_size * sizeof(char));
             if (!device_list->platform_node[i]->platform_name) {
                 av_log(&opencl_ctx, AV_LOG_WARNING,
                         "Could not allocate memory for device name: %s\n", av_opencl_errstr(status));
             } else {
                 status = clGetPlatformInfo(platform_ids[i], CL_PLATFORM_VENDOR,
                                            platform_name_size * sizeof(char),
                                            device_list->platform_node[i]->platform_name, NULL);
                 if (status != CL_SUCCESS) {
                     av_log(&opencl_ctx, AV_LOG_WARNING,
                             "Could not get platform name: %s\n", av_opencl_errstr(status));
                 }
             }
         }

         total_devices_num = 0;
         for (j = 0; j < FF_ARRAY_ELEMS(device_type); j++) {
             status = clGetDeviceIDs(device_list->platform_node[i]->platform_id,
                                     device_type[j], 0, NULL, &devices_num[j]);
             total_devices_num += devices_num[j];
         }

         device_list->platform_node[i]->device_node = av_mallocz_array(total_devices_num, sizeof(AVOpenCLDeviceNode *));

         if (!device_list->platform_node[i]->device_node) {
             ret = AVERROR(ENOMEM);
             goto end;
         }
         for (j = 0; j < FF_ARRAY_ELEMS(device_type); j++) {
             if (devices_num[j]) {

                 device_ids = av_mallocz_array(devices_num[j], sizeof(cl_device_id));

                 if (!device_ids) {
                     ret = AVERROR(ENOMEM);
                     goto end;
                 }
                 status = clGetDeviceIDs(device_list->platform_node[i]->platform_id, device_type[j],
                                         devices_num[j], device_ids, NULL);
                 if (status != CL_SUCCESS) {

                     av_log(&opencl_ctx, AV_LOG_WARNING,

                             "Could not get device ID: %s:\n", av_opencl_errstr(status));

                     av_freep(&device_ids);
                     continue;
                 }
                 for (k = 0; k < devices_num[j]; k++) {
                     device_num = device_list->platform_node[i]->device_num;
                     device_list->platform_node[i]->device_node[device_num] = av_mallocz(sizeof(AVOpenCLDeviceNode));
                     if (!device_list->platform_node[i]->device_node[device_num]) {
                         ret = AVERROR(ENOMEM);
                         goto end;
                     }
                     device_node = device_list->platform_node[i]->device_node[device_num];
                     device_node->device_id = device_ids[k];
                     device_node->device_type = device_type[j];
                     status = clGetDeviceInfo(device_node->device_id, CL_DEVICE_NAME,

                                              0, NULL, &device_name_size);
                     if (status != CL_SUCCESS) {
                         av_log(&opencl_ctx, AV_LOG_WARNING,
                                 "Could not get size of device name: %s\n", av_opencl_errstr(status));
                         continue;
                     }
                     device_node->device_name = av_malloc(device_name_size * sizeof(char));
                     if (!device_node->device_name) {
                         av_log(&opencl_ctx, AV_LOG_WARNING,
                                 "Could not allocate memory for device name: %s\n", av_opencl_errstr(status));
                         continue;
                     }
                     status = clGetDeviceInfo(device_node->device_id, CL_DEVICE_NAME,
                                              device_name_size * sizeof(char),
                                              device_node->device_name, NULL);

                     if (status != CL_SUCCESS) {

                         av_log(&opencl_ctx, AV_LOG_WARNING,

                                 "Could not get device name: %s\n", av_opencl_errstr(status));

                         continue;
                     }
                     device_list->platform_node[i]->device_num++;
                 }
                 av_freep(&device_ids);
             }
         }
     }
 end:
     av_freep(&platform_ids);
     av_freep(&devices_num);
     av_freep(&device_ids);
     if (ret < 0)
         free_device_list(device_list);
     return ret;
 }
 
 int av_opencl_get_device_list(AVOpenCLDeviceList **device_list)
 {
     int ret = 0;
     *device_list = av_mallocz(sizeof(AVOpenCLDeviceList));
     if (!(*device_list)) {

         av_log(&opencl_ctx, AV_LOG_ERROR, "Could not allocate opencl device list\n");

         return AVERROR(ENOMEM);
     }
     ret = get_device_list(*device_list);
     if (ret < 0) {

         av_log(&opencl_ctx, AV_LOG_ERROR, "Could not get device list from environment\n");

         free_device_list(*device_list);
         av_freep(device_list);
         return ret;
     }
     return ret;
 }
 
 void av_opencl_free_device_list(AVOpenCLDeviceList **device_list)
 {
     free_device_list(*device_list);
     av_freep(device_list);
 }
 

 static inline int init_opencl_mtx(void)

 {
 #if HAVE_THREADS
     if (!atomic_opencl_lock) {
         int err;
         pthread_mutex_t *tmp = av_malloc(sizeof(pthread_mutex_t));
         if (!tmp)
             return AVERROR(ENOMEM);
         if ((err = pthread_mutex_init(tmp, NULL))) {
             av_free(tmp);
             return AVERROR(err);
         }

         if (avpriv_atomic_ptr_cas((void * volatile *)&atomic_opencl_lock, NULL, tmp)) {

             pthread_mutex_destroy(tmp);
             av_free(tmp);
         }
     }
 #endif
     return 0;
 }
 

 int av_opencl_set_option(const char *key, const char *val)
 {

     int ret = init_opencl_mtx( );
     if (ret < 0)
         return ret;

     LOCK_OPENCL;

     if (!opencl_ctx.opt_init_flag) {
         av_opt_set_defaults(&opencl_ctx);
         opencl_ctx.opt_init_flag = 1;

     }

     ret = av_opt_set(&opencl_ctx, key, val, 0);

     UNLOCK_OPENCL;

     return ret;
 }
 
 int av_opencl_get_option(const char *key, uint8_t **out_val)
 {
     int ret = 0;

     LOCK_OPENCL;

     ret = av_opt_get(&opencl_ctx, key, 0, out_val);

     UNLOCK_OPENCL;

     return ret;
 }
 
 void av_opencl_free_option(void)
 {
     /*FIXME: free openclutils context*/

     LOCK_OPENCL;

     av_opt_free(&opencl_ctx);

     UNLOCK_OPENCL;

 }
 

 AVOpenCLExternalEnv *av_opencl_alloc_external_env(void)
 {
     AVOpenCLExternalEnv *ext = av_mallocz(sizeof(AVOpenCLExternalEnv));
     if (!ext) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not malloc external opencl environment data space\n");

     }
     return ext;
 }
 
 void av_opencl_free_external_env(AVOpenCLExternalEnv **ext_opencl_env)
 {
     av_freep(ext_opencl_env);
 }
 
 int av_opencl_register_kernel_code(const char *kernel_code)
 {

     int i, ret = init_opencl_mtx( );
     if (ret < 0)
         return ret;

     LOCK_OPENCL;

     if (opencl_ctx.kernel_code_count >= MAX_KERNEL_CODE_NUM) {
         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not register kernel code, maximum number of registered kernel code %d already reached\n",
                MAX_KERNEL_CODE_NUM);

         ret = AVERROR(EINVAL);
         goto end;
     }

     for (i = 0; i < opencl_ctx.kernel_code_count; i++) {
         if (opencl_ctx.kernel_code[i].kernel_string == kernel_code) {
             av_log(&opencl_ctx, AV_LOG_WARNING, "Same kernel code has been registered\n");

             goto end;
         }
     }

     opencl_ctx.kernel_code[opencl_ctx.kernel_code_count].kernel_string = kernel_code;
     opencl_ctx.kernel_code[opencl_ctx.kernel_code_count].is_compiled = 0;
     opencl_ctx.kernel_code_count++;

 end:
     UNLOCK_OPENCL;
     return ret;
 }
 

 cl_program av_opencl_compile(const char *program_name, const char *build_opts)

 {

     int i;

     cl_int status, build_status;

     int kernel_code_idx = 0;

     const char *kernel_source = NULL;

     size_t kernel_code_len;
     char* ptr = NULL;
     cl_program program = NULL;

     size_t log_size;
     char *log = NULL;

     LOCK_OPENCL;

     for (i = 0; i < opencl_ctx.kernel_code_count; i++) {
         // identify a program using a unique name within the kernel source
         ptr = av_stristr(opencl_ctx.kernel_code[i].kernel_string, program_name);
         if (ptr && !opencl_ctx.kernel_code[i].is_compiled) {
             kernel_source = opencl_ctx.kernel_code[i].kernel_string;
             kernel_code_len = strlen(opencl_ctx.kernel_code[i].kernel_string);
             kernel_code_idx = i;
             break;
         }
     }
     if (!kernel_source) {
         av_log(&opencl_ctx, AV_LOG_ERROR,
                "Unable to find OpenCL kernel source '%s'\n", program_name);

         goto end;
     }

 
     /* create a CL program from kernel source */
     program = clCreateProgramWithSource(opencl_ctx.context, 1, &kernel_source, &kernel_code_len, &status);
     if(status != CL_SUCCESS) {
         av_log(&opencl_ctx, AV_LOG_ERROR,
                "Unable to create OpenCL program '%s': %s\n", program_name, av_opencl_errstr(status));
         program = NULL;
         goto end;

     }

 
     build_status = clBuildProgram(program, 1, &(opencl_ctx.device_id), build_opts, NULL, NULL);
     status = clGetProgramBuildInfo(program, opencl_ctx.device_id,
                                    CL_PROGRAM_BUILD_LOG, 0, NULL, &log_size);

     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_WARNING,
                "Failed to get compilation log: %s\n",
                av_opencl_errstr(status));
     } else {
         log = av_malloc(log_size);
         if (log) {
             status = clGetProgramBuildInfo(program, opencl_ctx.device_id,
                                            CL_PROGRAM_BUILD_LOG, log_size,
                                            log, NULL);
             if (status != CL_SUCCESS) {
                 av_log(&opencl_ctx, AV_LOG_WARNING,
                        "Failed to get compilation log: %s\n",
                        av_opencl_errstr(status));
             } else {
                 int level = build_status == CL_SUCCESS ? AV_LOG_DEBUG :
                                                          AV_LOG_ERROR;
                 av_log(&opencl_ctx, level, "Compilation log:\n%s\n", log);
             }
         }
         av_freep(&log);
     }
     if (build_status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Compilation failed with OpenCL program '%s': %s\n",

                program_name, av_opencl_errstr(build_status));

         program = NULL;
         goto end;
     }
 
     opencl_ctx.kernel_code[kernel_code_idx].is_compiled = 1;

 end:
     UNLOCK_OPENCL;

     return program;
 }
 
 cl_command_queue av_opencl_get_command_queue(void)
 {
     return opencl_ctx.command_queue;
 }
 

 static int init_opencl_env(OpenclContext *opencl_ctx, AVOpenCLExternalEnv *ext_opencl_env)

 {
     cl_int status;
     cl_context_properties cps[3];

     int i, ret = 0;
     AVOpenCLDeviceNode *device_node = NULL;

     if (ext_opencl_env) {

         if (opencl_ctx->is_user_created)

             return 0;

         opencl_ctx->platform_id     = ext_opencl_env->platform_id;
         opencl_ctx->is_user_created = 1;
         opencl_ctx->command_queue   = ext_opencl_env->command_queue;
         opencl_ctx->context         = ext_opencl_env->context;
         opencl_ctx->device_id       = ext_opencl_env->device_id;
         opencl_ctx->device_type     = ext_opencl_env->device_type;

     } else {

         if (!opencl_ctx->is_user_created) {
             if (!opencl_ctx->device_list.platform_num) {
                 ret = get_device_list(&opencl_ctx->device_list);

                 if (ret < 0) {
                     return ret;
                 }

             }

             if (opencl_ctx->platform_idx >= 0) {
                 if (opencl_ctx->device_list.platform_num < opencl_ctx->platform_idx + 1) {
                     av_log(opencl_ctx, AV_LOG_ERROR, "User set platform index not exist\n");

                     return AVERROR(EINVAL);
                 }

                 if (!opencl_ctx->device_list.platform_node[opencl_ctx->platform_idx]->device_num) {
                     av_log(opencl_ctx, AV_LOG_ERROR, "No devices in user specific platform with index %d\n",
                            opencl_ctx->platform_idx);

                     return AVERROR(EINVAL);

                 }

                 opencl_ctx->platform_id = opencl_ctx->device_list.platform_node[opencl_ctx->platform_idx]->platform_id;

             } else {
                 /* get a usable platform by default*/

                 for (i = 0; i < opencl_ctx->device_list.platform_num; i++) {
                     if (opencl_ctx->device_list.platform_node[i]->device_num) {
                         opencl_ctx->platform_id = opencl_ctx->device_list.platform_node[i]->platform_id;
                         opencl_ctx->platform_idx = i;

                         break;

                     }
                 }
             }

             if (!opencl_ctx->platform_id) {
                 av_log(opencl_ctx, AV_LOG_ERROR, "Could not get OpenCL platforms\n");

                 return AVERROR_EXTERNAL;

             }

             /* get a usable device*/

             if (opencl_ctx->device_idx >= 0) {
                 if (opencl_ctx->device_list.platform_node[opencl_ctx->platform_idx]->device_num < opencl_ctx->device_idx + 1) {
                     av_log(opencl_ctx, AV_LOG_ERROR,
                            "Could not get OpenCL device idx %d in the user set platform\n", opencl_ctx->platform_idx);

                     return AVERROR(EINVAL);

                 }

             } else {

                 opencl_ctx->device_idx = 0;

             }
 

             device_node = opencl_ctx->device_list.platform_node[opencl_ctx->platform_idx]->device_node[opencl_ctx->device_idx];
             opencl_ctx->device_id = device_node->device_id;
             opencl_ctx->device_type = device_node->device_type;

             /*
              * Use available platform.
              */

             av_log(opencl_ctx, AV_LOG_VERBOSE, "Platform Name: %s, Device Name: %s\n",

                    opencl_ctx->device_list.platform_node[opencl_ctx->platform_idx]->platform_name,

                    device_node->device_name);

             cps[0] = CL_CONTEXT_PLATFORM;

             cps[1] = (cl_context_properties)opencl_ctx->platform_id;

             cps[2] = 0;

 
             opencl_ctx->context = clCreateContextFromType(cps, opencl_ctx->device_type,

                                                        NULL, NULL, &status);

             if (status != CL_SUCCESS) {

                 av_log(opencl_ctx, AV_LOG_ERROR,

                        "Could not get OpenCL context from device type: %s\n", av_opencl_errstr(status));

                 return AVERROR_EXTERNAL;

             }

             opencl_ctx->command_queue = clCreateCommandQueue(opencl_ctx->context, opencl_ctx->device_id,

                                                           0, &status);
             if (status != CL_SUCCESS) {

                 av_log(opencl_ctx, AV_LOG_ERROR,

                        "Could not create OpenCL command queue: %s\n", av_opencl_errstr(status));

                 return AVERROR_EXTERNAL;

             }
         }
     }
     return ret;
 }
 

 int av_opencl_init(AVOpenCLExternalEnv *ext_opencl_env)

 {

     int ret = init_opencl_mtx( );
     if (ret < 0)
         return ret;

     LOCK_OPENCL;

     if (!opencl_ctx.init_count) {
         if (!opencl_ctx.opt_init_flag) {
             av_opt_set_defaults(&opencl_ctx);
             opencl_ctx.opt_init_flag = 1;

         }

         ret = init_opencl_env(&opencl_ctx, ext_opencl_env);

         if (ret < 0)
             goto end;

         if (opencl_ctx.kernel_code_count <= 0) {
             av_log(&opencl_ctx, AV_LOG_ERROR,
                    "No kernel code is registered, compile kernel file failed\n");
             ret = AVERROR(EINVAL);
             goto end;
         }

     }

     opencl_ctx.init_count++;

 end:

     UNLOCK_OPENCL;

     return ret;
 }
 
 void av_opencl_uninit(void)
 {

     int i;

     cl_int status;

     LOCK_OPENCL;

     opencl_ctx.init_count--;
     if (opencl_ctx.is_user_created)

         goto end;

     if (opencl_ctx.init_count > 0)

         goto end;

     if (opencl_ctx.command_queue) {
         status = clReleaseCommandQueue(opencl_ctx.command_queue);

         if (status != CL_SUCCESS) {

             av_log(&opencl_ctx, AV_LOG_ERROR,

                    "Could not release OpenCL command queue: %s\n", av_opencl_errstr(status));

         }

         opencl_ctx.command_queue = NULL;

     }

     if (opencl_ctx.context) {
         status = clReleaseContext(opencl_ctx.context);

         if (status != CL_SUCCESS) {

             av_log(&opencl_ctx, AV_LOG_ERROR,

                    "Could not release OpenCL context: %s\n", av_opencl_errstr(status));

         }

         opencl_ctx.context = NULL;

     }

     for (i = 0; i < opencl_ctx.kernel_code_count; i++) {
         opencl_ctx.kernel_code[i].is_compiled = 0;
     }

     free_device_list(&opencl_ctx.device_list);

 end:

     if (opencl_ctx.init_count <= 0)

         av_opt_free(&opencl_ctx); //FIXME: free openclutils context

     UNLOCK_OPENCL;

 }
 
 int av_opencl_buffer_create(cl_mem *cl_buf, size_t cl_buf_size, int flags, void *host_ptr)
 {
     cl_int status;

     *cl_buf = clCreateBuffer(opencl_ctx.context, flags, cl_buf_size, host_ptr, &status);

     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR, "Could not create OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     return 0;
 }
 
 void av_opencl_buffer_release(cl_mem *cl_buf)
 {
     cl_int status = 0;
     if (!cl_buf)
         return;
     status = clReleaseMemObject(*cl_buf);
     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not release OpenCL buffer: %s\n", av_opencl_errstr(status));

     }
     memset(cl_buf, 0, sizeof(*cl_buf));
 }
 
 int av_opencl_buffer_write(cl_mem dst_cl_buf, uint8_t *src_buf, size_t buf_size)
 {
     cl_int status;

     void *mapped = clEnqueueMapBuffer(opencl_ctx.command_queue, dst_cl_buf,
                                       CL_TRUE, CL_MAP_WRITE, 0, sizeof(uint8_t) * buf_size,

                                       0, NULL, NULL, &status);
 
     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not map OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     memcpy(mapped, src_buf, buf_size);
 

     status = clEnqueueUnmapMemObject(opencl_ctx.command_queue, dst_cl_buf, mapped, 0, NULL, NULL);

     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not unmap OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     return 0;
 }
 
 int av_opencl_buffer_read(uint8_t *dst_buf, cl_mem src_cl_buf, size_t buf_size)
 {
     cl_int status;

     void *mapped = clEnqueueMapBuffer(opencl_ctx.command_queue, src_cl_buf,
                                       CL_TRUE, CL_MAP_READ, 0, buf_size,

                                       0, NULL, NULL, &status);
 
     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not map OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     memcpy(dst_buf, mapped, buf_size);
 

     status = clEnqueueUnmapMemObject(opencl_ctx.command_queue, src_cl_buf, mapped, 0, NULL, NULL);

     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not unmap OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     return 0;
 }
 
 int av_opencl_buffer_write_image(cl_mem dst_cl_buf, size_t cl_buffer_size, int dst_cl_offset,

                                  uint8_t **src_data, int *plane_size, int plane_num)

 {
     int i, buffer_size = 0;
     uint8_t *temp;
     cl_int status;
     void *mapped;
     if ((unsigned int)plane_num > 8) {
         return AVERROR(EINVAL);
     }
     for (i = 0;i < plane_num;i++) {
         buffer_size += plane_size[i];
     }
     if (buffer_size > cl_buffer_size) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Cannot write image to OpenCL buffer: buffer too small\n");

         return AVERROR(EINVAL);
     }

     mapped = clEnqueueMapBuffer(opencl_ctx.command_queue, dst_cl_buf,
                                 CL_TRUE, CL_MAP_WRITE, 0, buffer_size + dst_cl_offset,

                                 0, NULL, NULL, &status);

     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not map OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     temp = mapped;
     temp += dst_cl_offset;
     for (i = 0; i < plane_num; i++) {
         memcpy(temp, src_data[i], plane_size[i]);
         temp += plane_size[i];
     }

     status = clEnqueueUnmapMemObject(opencl_ctx.command_queue, dst_cl_buf, mapped, 0, NULL, NULL);

     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not unmap OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     return 0;
 }
 
 int av_opencl_buffer_read_image(uint8_t **dst_data, int *plane_size, int plane_num,

                                 cl_mem src_cl_buf, size_t cl_buffer_size)

 {
     int i,buffer_size = 0,ret = 0;
     uint8_t *temp;
     void *mapped;
     cl_int status;
     if ((unsigned int)plane_num > 8) {
         return AVERROR(EINVAL);
     }

     for (i = 0; i < plane_num; i++) {

         buffer_size += plane_size[i];
     }
     if (buffer_size > cl_buffer_size) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Cannot write image to CPU buffer: OpenCL buffer too small\n");

         return AVERROR(EINVAL);
     }

     mapped = clEnqueueMapBuffer(opencl_ctx.command_queue, src_cl_buf,
                                 CL_TRUE, CL_MAP_READ, 0, buffer_size,

                                 0, NULL, NULL, &status);

 
     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not map OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     temp = mapped;
     if (ret >= 0) {

         for (i = 0; i < plane_num; i++) {

             memcpy(dst_data[i], temp, plane_size[i]);
             temp += plane_size[i];
         }
     }

     status = clEnqueueUnmapMemObject(opencl_ctx.command_queue, src_cl_buf, mapped, 0, NULL, NULL);

     if (status != CL_SUCCESS) {

         av_log(&opencl_ctx, AV_LOG_ERROR,

                "Could not unmap OpenCL buffer: %s\n", av_opencl_errstr(status));

         return AVERROR_EXTERNAL;
     }
     return 0;
 }

 
 int64_t av_opencl_benchmark(AVOpenCLDeviceNode *device_node, cl_platform_id platform,
                             int64_t (*benchmark)(AVOpenCLExternalEnv *ext_opencl_env))
 {
     int64_t ret = 0;
     cl_int status;
     cl_context_properties cps[3];
     AVOpenCLExternalEnv *ext_opencl_env = NULL;
 
     ext_opencl_env = av_opencl_alloc_external_env();
     ext_opencl_env->device_id = device_node->device_id;
     ext_opencl_env->device_type = device_node->device_type;
     av_log(&opencl_ctx, AV_LOG_VERBOSE, "Performing test on OpenCL device %s\n",
            device_node->device_name);
 
     cps[0] = CL_CONTEXT_PLATFORM;
     cps[1] = (cl_context_properties)platform;
     cps[2] = 0;
     ext_opencl_env->context = clCreateContextFromType(cps, ext_opencl_env->device_type,
                                                       NULL, NULL, &status);
     if (status != CL_SUCCESS || !ext_opencl_env->context) {
         ret = AVERROR_EXTERNAL;
         goto end;
     }
     ext_opencl_env->command_queue = clCreateCommandQueue(ext_opencl_env->context,
                                                          ext_opencl_env->device_id, 0, &status);
     if (status != CL_SUCCESS || !ext_opencl_env->command_queue) {
         ret = AVERROR_EXTERNAL;
         goto end;
     }
     ret = benchmark(ext_opencl_env);
     if (ret < 0)
         av_log(&opencl_ctx, AV_LOG_ERROR, "Benchmark failed with OpenCL device %s\n",
                device_node->device_name);
 end:
     if (ext_opencl_env->command_queue)
         clReleaseCommandQueue(ext_opencl_env->command_queue);
     if (ext_opencl_env->context)
         clReleaseContext(ext_opencl_env->context);
     av_opencl_free_external_env(&ext_opencl_env);
     return ret;
 }