/*

  * 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
  */
 
 /**
  * @file
  * scale video filter
  */
 
 #include <nppi.h>
 #include <stdio.h>
 #include <string.h>
 
 #include "libavutil/avstring.h"
 #include "libavutil/common.h"
 #include "libavutil/hwcontext.h"

 #include "libavutil/hwcontext_cuda_internal.h"

 #include "libavutil/internal.h"
 #include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
 
 #include "avfilter.h"
 #include "formats.h"
 #include "internal.h"

 #include "scale.h"

 #include "video.h"
 
 static const enum AVPixelFormat supported_formats[] = {
     AV_PIX_FMT_YUV420P,
     AV_PIX_FMT_NV12,
     AV_PIX_FMT_YUV444P,
 };
 
 static const enum AVPixelFormat deinterleaved_formats[][2] = {
     { AV_PIX_FMT_NV12, AV_PIX_FMT_YUV420P },
 };
 
 enum ScaleStage {
     STAGE_DEINTERLEAVE,
     STAGE_RESIZE,
     STAGE_INTERLEAVE,
     STAGE_NB,
 };
 
 typedef struct NPPScaleStageContext {
     int stage_needed;
     enum AVPixelFormat in_fmt;
     enum AVPixelFormat out_fmt;
 
     struct {
         int width;
         int height;
     } planes_in[3], planes_out[3];
 
     AVBufferRef *frames_ctx;
     AVFrame     *frame;
 } NPPScaleStageContext;
 
 typedef struct NPPScaleContext {
     const AVClass *class;
 
     NPPScaleStageContext stages[STAGE_NB];
     AVFrame *tmp_frame;
     int passthrough;
 
     int shift_width, shift_height;
 
     /**
      * New dimensions. Special values are:
      *   0 = original width/height
      *  -1 = keep original aspect
      */
     int w, h;
 
     /**
      * Output sw format. AV_PIX_FMT_NONE for no conversion.
      */
     enum AVPixelFormat format;
 
     char *w_expr;               ///< width  expression string
     char *h_expr;               ///< height expression string
     char *format_str;
 
     int interp_algo;
 } NPPScaleContext;
 
 static int nppscale_init(AVFilterContext *ctx)
 {
     NPPScaleContext *s = ctx->priv;
     int i;
 
     if (!strcmp(s->format_str, "same")) {
         s->format = AV_PIX_FMT_NONE;
     } else {
         s->format = av_get_pix_fmt(s->format_str);
         if (s->format == AV_PIX_FMT_NONE) {
             av_log(ctx, AV_LOG_ERROR, "Unrecognized pixel format: %s\n", s->format_str);
             return AVERROR(EINVAL);
         }
     }
 
     for (i = 0; i < FF_ARRAY_ELEMS(s->stages); i++) {
         s->stages[i].frame = av_frame_alloc();
         if (!s->stages[i].frame)
             return AVERROR(ENOMEM);
     }
     s->tmp_frame = av_frame_alloc();
     if (!s->tmp_frame)
         return AVERROR(ENOMEM);
 
     return 0;
 }
 
 static void nppscale_uninit(AVFilterContext *ctx)
 {
     NPPScaleContext *s = ctx->priv;
     int i;
 
     for (i = 0; i < FF_ARRAY_ELEMS(s->stages); i++) {
         av_frame_free(&s->stages[i].frame);
         av_buffer_unref(&s->stages[i].frames_ctx);
     }
     av_frame_free(&s->tmp_frame);
 }
 
 static int nppscale_query_formats(AVFilterContext *ctx)
 {
     static const enum AVPixelFormat pixel_formats[] = {
         AV_PIX_FMT_CUDA, AV_PIX_FMT_NONE,
     };

     AVFilterFormats *pix_fmts = ff_make_format_list(pixel_formats);

     return ff_set_common_formats(ctx, pix_fmts);

 }
 
 static int init_stage(NPPScaleStageContext *stage, AVBufferRef *device_ctx)
 {
     AVBufferRef *out_ref = NULL;
     AVHWFramesContext *out_ctx;
     int in_sw, in_sh, out_sw, out_sh;
     int ret, i;
 
     av_pix_fmt_get_chroma_sub_sample(stage->in_fmt,  &in_sw,  &in_sh);
     av_pix_fmt_get_chroma_sub_sample(stage->out_fmt, &out_sw, &out_sh);
     if (!stage->planes_out[0].width) {
         stage->planes_out[0].width  = stage->planes_in[0].width;
         stage->planes_out[0].height = stage->planes_in[0].height;
     }
 
     for (i = 1; i < FF_ARRAY_ELEMS(stage->planes_in); i++) {
         stage->planes_in[i].width   = stage->planes_in[0].width   >> in_sw;
         stage->planes_in[i].height  = stage->planes_in[0].height  >> in_sh;
         stage->planes_out[i].width  = stage->planes_out[0].width  >> out_sw;
         stage->planes_out[i].height = stage->planes_out[0].height >> out_sh;
     }
 
     out_ref = av_hwframe_ctx_alloc(device_ctx);
     if (!out_ref)
         return AVERROR(ENOMEM);
     out_ctx = (AVHWFramesContext*)out_ref->data;
 
     out_ctx->format    = AV_PIX_FMT_CUDA;
     out_ctx->sw_format = stage->out_fmt;
     out_ctx->width     = FFALIGN(stage->planes_out[0].width,  32);
     out_ctx->height    = FFALIGN(stage->planes_out[0].height, 32);
 
     ret = av_hwframe_ctx_init(out_ref);
     if (ret < 0)
         goto fail;
 
     av_frame_unref(stage->frame);
     ret = av_hwframe_get_buffer(out_ref, stage->frame, 0);
     if (ret < 0)
         goto fail;
 
     stage->frame->width  = stage->planes_out[0].width;
     stage->frame->height = stage->planes_out[0].height;
 
     av_buffer_unref(&stage->frames_ctx);
     stage->frames_ctx = out_ref;
 
     return 0;
 fail:
     av_buffer_unref(&out_ref);
     return ret;
 }
 
 static int format_is_supported(enum AVPixelFormat fmt)
 {
     int i;
 
     for (i = 0; i < FF_ARRAY_ELEMS(supported_formats); i++)
         if (supported_formats[i] == fmt)
             return 1;
     return 0;
 }
 
 static enum AVPixelFormat get_deinterleaved_format(enum AVPixelFormat fmt)
 {
     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(fmt);
     int i, planes;
 
     planes = av_pix_fmt_count_planes(fmt);
     if (planes == desc->nb_components)
         return fmt;
     for (i = 0; i < FF_ARRAY_ELEMS(deinterleaved_formats); i++)
         if (deinterleaved_formats[i][0] == fmt)
             return deinterleaved_formats[i][1];
     return AV_PIX_FMT_NONE;
 }
 
 static int init_processing_chain(AVFilterContext *ctx, int in_width, int in_height,
                                  int out_width, int out_height)
 {
     NPPScaleContext *s = ctx->priv;
 
     AVHWFramesContext *in_frames_ctx;
 
     enum AVPixelFormat in_format;
     enum AVPixelFormat out_format;
     enum AVPixelFormat in_deinterleaved_format;
     enum AVPixelFormat out_deinterleaved_format;
 
     int i, ret, last_stage = -1;
 
     /* check that we have a hw context */
     if (!ctx->inputs[0]->hw_frames_ctx) {
         av_log(ctx, AV_LOG_ERROR, "No hw context provided on input\n");
         return AVERROR(EINVAL);
     }
     in_frames_ctx = (AVHWFramesContext*)ctx->inputs[0]->hw_frames_ctx->data;
     in_format     = in_frames_ctx->sw_format;
     out_format    = (s->format == AV_PIX_FMT_NONE) ? in_format : s->format;
 
     if (!format_is_supported(in_format)) {
         av_log(ctx, AV_LOG_ERROR, "Unsupported input format: %s\n",
                av_get_pix_fmt_name(in_format));
         return AVERROR(ENOSYS);
     }
     if (!format_is_supported(out_format)) {
         av_log(ctx, AV_LOG_ERROR, "Unsupported output format: %s\n",
                av_get_pix_fmt_name(out_format));
         return AVERROR(ENOSYS);
     }
 
     in_deinterleaved_format  = get_deinterleaved_format(in_format);
     out_deinterleaved_format = get_deinterleaved_format(out_format);
     if (in_deinterleaved_format  == AV_PIX_FMT_NONE ||
         out_deinterleaved_format == AV_PIX_FMT_NONE)
         return AVERROR_BUG;
 
     /* figure out which stages need to be done */
     if (in_width != out_width || in_height != out_height ||

         in_deinterleaved_format != out_deinterleaved_format) {

         s->stages[STAGE_RESIZE].stage_needed = 1;
 

         if (s->interp_algo == NPPI_INTER_SUPER &&
             (out_width > in_width && out_height > in_height)) {
             s->interp_algo = NPPI_INTER_LANCZOS;
             av_log(ctx, AV_LOG_WARNING, "super-sampling not supported for output dimensions, using lanczos instead.\n");
         }
         if (s->interp_algo == NPPI_INTER_SUPER &&
             !(out_width < in_width && out_height < in_height)) {
             s->interp_algo = NPPI_INTER_CUBIC;
             av_log(ctx, AV_LOG_WARNING, "super-sampling not supported for output dimensions, using cubic instead.\n");
         }
     }
 

     if (!s->stages[STAGE_RESIZE].stage_needed && in_format == out_format)
         s->passthrough = 1;
 
     if (!s->passthrough) {
         if (in_format != in_deinterleaved_format)
             s->stages[STAGE_DEINTERLEAVE].stage_needed = 1;
         if (out_format != out_deinterleaved_format)
             s->stages[STAGE_INTERLEAVE].stage_needed = 1;
     }
 
     s->stages[STAGE_DEINTERLEAVE].in_fmt              = in_format;
     s->stages[STAGE_DEINTERLEAVE].out_fmt             = in_deinterleaved_format;
     s->stages[STAGE_DEINTERLEAVE].planes_in[0].width  = in_width;
     s->stages[STAGE_DEINTERLEAVE].planes_in[0].height = in_height;
 
     s->stages[STAGE_RESIZE].in_fmt               = in_deinterleaved_format;
     s->stages[STAGE_RESIZE].out_fmt              = out_deinterleaved_format;
     s->stages[STAGE_RESIZE].planes_in[0].width   = in_width;
     s->stages[STAGE_RESIZE].planes_in[0].height  = in_height;
     s->stages[STAGE_RESIZE].planes_out[0].width  = out_width;
     s->stages[STAGE_RESIZE].planes_out[0].height = out_height;
 
     s->stages[STAGE_INTERLEAVE].in_fmt              = out_deinterleaved_format;
     s->stages[STAGE_INTERLEAVE].out_fmt             = out_format;
     s->stages[STAGE_INTERLEAVE].planes_in[0].width  = out_width;
     s->stages[STAGE_INTERLEAVE].planes_in[0].height = out_height;
 
     /* init the hardware contexts */
     for (i = 0; i < FF_ARRAY_ELEMS(s->stages); i++) {
         if (!s->stages[i].stage_needed)
             continue;
 
         ret = init_stage(&s->stages[i], in_frames_ctx->device_ref);
         if (ret < 0)
             return ret;
 
         last_stage = i;
     }
 

     if (last_stage >= 0)

         ctx->outputs[0]->hw_frames_ctx = av_buffer_ref(s->stages[last_stage].frames_ctx);

     else
         ctx->outputs[0]->hw_frames_ctx = av_buffer_ref(ctx->inputs[0]->hw_frames_ctx);

     if (!ctx->outputs[0]->hw_frames_ctx)
         return AVERROR(ENOMEM);
 
     return 0;
 }
 
 static int nppscale_config_props(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;
     AVFilterLink *inlink = outlink->src->inputs[0];

     NPPScaleContext *s = ctx->priv;
     int w, h;

     int ret;
 

     if ((ret = ff_scale_eval_dimensions(s,
                                         s->w_expr, s->h_expr,
                                         inlink, outlink,
                                         &w, &h)) < 0)

         goto fail;
 

     if (((int64_t)h * inlink->w) > INT_MAX  ||
         ((int64_t)w * inlink->h) > INT_MAX)

         av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
 
     outlink->w = w;
     outlink->h = h;
 
     ret = init_processing_chain(ctx, inlink->w, inlink->h, w, h);
     if (ret < 0)
         return ret;
 
     av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d -> w:%d h:%d\n",
            inlink->w, inlink->h, outlink->w, outlink->h);
 
     if (inlink->sample_aspect_ratio.num)
         outlink->sample_aspect_ratio = av_mul_q((AVRational){outlink->h*inlink->w,
                                                              outlink->w*inlink->h},
                                                 inlink->sample_aspect_ratio);
     else
         outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
 
     return 0;
 
 fail:
     return ret;
 }
 
 static int nppscale_deinterleave(AVFilterContext *ctx, NPPScaleStageContext *stage,
                                  AVFrame *out, AVFrame *in)
 {
     AVHWFramesContext *in_frames_ctx = (AVHWFramesContext*)in->hw_frames_ctx->data;
     NppStatus err;
 
     switch (in_frames_ctx->sw_format) {
     case AV_PIX_FMT_NV12:
         err = nppiYCbCr420_8u_P2P3R(in->data[0], in->linesize[0],
                                     in->data[1], in->linesize[1],
                                     out->data, out->linesize,
                                     (NppiSize){ in->width, in->height });
         break;
     default:
         return AVERROR_BUG;
     }
     if (err != NPP_SUCCESS) {
         av_log(ctx, AV_LOG_ERROR, "NPP deinterleave error: %d\n", err);
         return AVERROR_UNKNOWN;
     }
 
     return 0;
 }
 
 static int nppscale_resize(AVFilterContext *ctx, NPPScaleStageContext *stage,
                            AVFrame *out, AVFrame *in)
 {
     NPPScaleContext *s = ctx->priv;
     NppStatus err;
     int i;
 

     for (i = 0; i < FF_ARRAY_ELEMS(stage->planes_in) && i < FF_ARRAY_ELEMS(in->data) && in->data[i]; i++) {

         int iw = stage->planes_in[i].width;
         int ih = stage->planes_in[i].height;
         int ow = stage->planes_out[i].width;
         int oh = stage->planes_out[i].height;
 
         err = nppiResizeSqrPixel_8u_C1R(in->data[i], (NppiSize){ iw, ih },
                                         in->linesize[i], (NppiRect){ 0, 0, iw, ih },
                                         out->data[i], out->linesize[i],
                                         (NppiRect){ 0, 0, ow, oh },
                                         (double)ow / iw, (double)oh / ih,
                                         0.0, 0.0, s->interp_algo);
         if (err != NPP_SUCCESS) {
             av_log(ctx, AV_LOG_ERROR, "NPP resize error: %d\n", err);
             return AVERROR_UNKNOWN;
         }
     }
 
     return 0;
 }
 
 static int nppscale_interleave(AVFilterContext *ctx, NPPScaleStageContext *stage,
                                AVFrame *out, AVFrame *in)
 {
     AVHWFramesContext *out_frames_ctx = (AVHWFramesContext*)out->hw_frames_ctx->data;
     NppStatus err;
 
     switch (out_frames_ctx->sw_format) {
     case AV_PIX_FMT_NV12:
         err = nppiYCbCr420_8u_P3P2R((const uint8_t**)in->data,
                                     in->linesize,
                                     out->data[0], out->linesize[0],
                                     out->data[1], out->linesize[1],
                                     (NppiSize){ in->width, in->height });
         break;
     default:
         return AVERROR_BUG;
     }
     if (err != NPP_SUCCESS) {
         av_log(ctx, AV_LOG_ERROR, "NPP deinterleave error: %d\n", err);
         return AVERROR_UNKNOWN;
     }
 
     return 0;
 }
 
 static int (*const nppscale_process[])(AVFilterContext *ctx, NPPScaleStageContext *stage,
                                        AVFrame *out, AVFrame *in) = {
     [STAGE_DEINTERLEAVE] = nppscale_deinterleave,
     [STAGE_RESIZE]       = nppscale_resize,
     [STAGE_INTERLEAVE]   = nppscale_interleave,
 };
 
 static int nppscale_scale(AVFilterContext *ctx, AVFrame *out, AVFrame *in)
 {
     NPPScaleContext *s = ctx->priv;
     AVFrame *src = in;
     int i, ret, last_stage = -1;
 
     for (i = 0; i < FF_ARRAY_ELEMS(s->stages); i++) {
         if (!s->stages[i].stage_needed)
             continue;
 
         ret = nppscale_process[i](ctx, &s->stages[i], s->stages[i].frame, src);
         if (ret < 0)
             return ret;
 
         src        = s->stages[i].frame;
         last_stage = i;
     }
 
     if (last_stage < 0)
         return AVERROR_BUG;
     ret = av_hwframe_get_buffer(src->hw_frames_ctx, s->tmp_frame, 0);
     if (ret < 0)
         return ret;
 
     av_frame_move_ref(out, src);
     av_frame_move_ref(src, s->tmp_frame);
 
     ret = av_frame_copy_props(out, in);
     if (ret < 0)
         return ret;
 
     return 0;
 }
 
 static int nppscale_filter_frame(AVFilterLink *link, AVFrame *in)
 {
     AVFilterContext              *ctx = link->dst;
     NPPScaleContext                *s = ctx->priv;
     AVFilterLink             *outlink = ctx->outputs[0];
     AVHWFramesContext     *frames_ctx = (AVHWFramesContext*)outlink->hw_frames_ctx->data;
     AVCUDADeviceContext *device_hwctx = frames_ctx->device_ctx->hwctx;
 
     AVFrame *out = NULL;
     CUresult err;
     CUcontext dummy;
     int ret = 0;
 
     if (s->passthrough)
         return ff_filter_frame(outlink, in);
 
     out = av_frame_alloc();
     if (!out) {
         ret = AVERROR(ENOMEM);
         goto fail;
     }
 

     err = device_hwctx->internal->cuda_dl->cuCtxPushCurrent(device_hwctx->cuda_ctx);

     if (err != CUDA_SUCCESS) {
         ret = AVERROR_UNKNOWN;
         goto fail;
     }
 
     ret = nppscale_scale(ctx, out, in);
 

     device_hwctx->internal->cuda_dl->cuCtxPopCurrent(&dummy);

     if (ret < 0)
         goto fail;
 

     av_reduce(&out->sample_aspect_ratio.num, &out->sample_aspect_ratio.den,
               (int64_t)in->sample_aspect_ratio.num * outlink->h * link->w,
               (int64_t)in->sample_aspect_ratio.den * outlink->w * link->h,
               INT_MAX);
 

     av_frame_free(&in);
     return ff_filter_frame(outlink, out);
 fail:
     av_frame_free(&in);
     av_frame_free(&out);
     return ret;
 }
 
 #define OFFSET(x) offsetof(NPPScaleContext, x)

 #define FLAGS (AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM)

 static const AVOption options[] = {
     { "w",      "Output video width",  OFFSET(w_expr),     AV_OPT_TYPE_STRING, { .str = "iw"   }, .flags = FLAGS },
     { "h",      "Output video height", OFFSET(h_expr),     AV_OPT_TYPE_STRING, { .str = "ih"   }, .flags = FLAGS },
     { "format", "Output pixel format", OFFSET(format_str), AV_OPT_TYPE_STRING, { .str = "same" }, .flags = FLAGS },
 
     { "interp_algo", "Interpolation algorithm used for resizing", OFFSET(interp_algo), AV_OPT_TYPE_INT, { .i64 = NPPI_INTER_CUBIC }, 0, INT_MAX, FLAGS, "interp_algo" },
         { "nn",                 "nearest neighbour",                 0, AV_OPT_TYPE_CONST, { .i64 = NPPI_INTER_NN                 }, 0, 0, FLAGS, "interp_algo" },
         { "linear",             "linear",                            0, AV_OPT_TYPE_CONST, { .i64 = NPPI_INTER_LINEAR             }, 0, 0, FLAGS, "interp_algo" },
         { "cubic",              "cubic",                             0, AV_OPT_TYPE_CONST, { .i64 = NPPI_INTER_CUBIC              }, 0, 0, FLAGS, "interp_algo" },
         { "cubic2p_bspline",    "2-parameter cubic (B=1, C=0)",      0, AV_OPT_TYPE_CONST, { .i64 = NPPI_INTER_CUBIC2P_BSPLINE    }, 0, 0, FLAGS, "interp_algo" },
         { "cubic2p_catmullrom", "2-parameter cubic (B=0, C=1/2)",    0, AV_OPT_TYPE_CONST, { .i64 = NPPI_INTER_CUBIC2P_CATMULLROM }, 0, 0, FLAGS, "interp_algo" },
         { "cubic2p_b05c03",     "2-parameter cubic (B=1/2, C=3/10)", 0, AV_OPT_TYPE_CONST, { .i64 = NPPI_INTER_CUBIC2P_B05C03     }, 0, 0, FLAGS, "interp_algo" },
         { "super",              "supersampling",                     0, AV_OPT_TYPE_CONST, { .i64 = NPPI_INTER_SUPER              }, 0, 0, FLAGS, "interp_algo" },
         { "lanczos",            "Lanczos",                           0, AV_OPT_TYPE_CONST, { .i64 = NPPI_INTER_LANCZOS            }, 0, 0, FLAGS, "interp_algo" },
     { NULL },
 };
 
 static const AVClass nppscale_class = {
     .class_name = "nppscale",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 static const AVFilterPad nppscale_inputs[] = {
     {
         .name        = "default",
         .type        = AVMEDIA_TYPE_VIDEO,
         .filter_frame = nppscale_filter_frame,
     },
     { NULL }
 };
 
 static const AVFilterPad nppscale_outputs[] = {
     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
         .config_props = nppscale_config_props,
     },
     { NULL }
 };
 
 AVFilter ff_vf_scale_npp = {
     .name      = "scale_npp",
     .description = NULL_IF_CONFIG_SMALL("NVIDIA Performance Primitives video "
                                         "scaling and format conversion"),
 
     .init          = nppscale_init,
     .uninit        = nppscale_uninit,
     .query_formats = nppscale_query_formats,
 
     .priv_size = sizeof(NPPScaleContext),
     .priv_class = &nppscale_class,
 
     .inputs    = nppscale_inputs,
     .outputs   = nppscale_outputs,

 
     .flags_internal = FF_FILTER_FLAG_HWFRAME_AWARE,

 };