yading@10: /*
yading@10:  * Copyright (c) 2007 Bobby Bingham
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * scale video filter
yading@10:  */
yading@10: 
yading@10: #include <stdio.h>
yading@10: #include <string.h>
yading@10: 
yading@10: #include "avfilter.h"
yading@10: #include "formats.h"
yading@10: #include "internal.h"
yading@10: #include "video.h"
yading@10: #include "libavutil/avstring.h"
yading@10: #include "libavutil/eval.h"
yading@10: #include "libavutil/internal.h"
yading@10: #include "libavutil/mathematics.h"
yading@10: #include "libavutil/opt.h"
yading@10: #include "libavutil/parseutils.h"
yading@10: #include "libavutil/pixdesc.h"
yading@10: #include "libavutil/imgutils.h"
yading@10: #include "libavutil/avassert.h"
yading@10: #include "libswscale/swscale.h"
yading@10: 
yading@10: static const char *const var_names[] = {
yading@10:     "in_w",   "iw",
yading@10:     "in_h",   "ih",
yading@10:     "out_w",  "ow",
yading@10:     "out_h",  "oh",
yading@10:     "a",
yading@10:     "sar",
yading@10:     "dar",
yading@10:     "hsub",
yading@10:     "vsub",
yading@10:     NULL
yading@10: };
yading@10: 
yading@10: enum var_name {
yading@10:     VAR_IN_W,   VAR_IW,
yading@10:     VAR_IN_H,   VAR_IH,
yading@10:     VAR_OUT_W,  VAR_OW,
yading@10:     VAR_OUT_H,  VAR_OH,
yading@10:     VAR_A,
yading@10:     VAR_SAR,
yading@10:     VAR_DAR,
yading@10:     VAR_HSUB,
yading@10:     VAR_VSUB,
yading@10:     VARS_NB
yading@10: };
yading@10: 
yading@10: typedef struct {
yading@10:     const AVClass *class;
yading@10:     struct SwsContext *sws;     ///< software scaler context
yading@10:     struct SwsContext *isws[2]; ///< software scaler context for interlaced material
yading@10: 
yading@10:     /**
yading@10:      * New dimensions. Special values are:
yading@10:      *   0 = original width/height
yading@10:      *  -1 = keep original aspect
yading@10:      */
yading@10:     int w, h;
yading@10:     char *size_str;
yading@10:     unsigned int flags;         ///sws flags
yading@10: 
yading@10:     int hsub, vsub;             ///< chroma subsampling
yading@10:     int slice_y;                ///< top of current output slice
yading@10:     int input_is_pal;           ///< set to 1 if the input format is paletted
yading@10:     int output_is_pal;          ///< set to 1 if the output format is paletted
yading@10:     int interlaced;
yading@10: 
yading@10:     char *w_expr;               ///< width  expression string
yading@10:     char *h_expr;               ///< height expression string
yading@10:     char *flags_str;
yading@10: } ScaleContext;
yading@10: 
yading@10: static av_cold int init(AVFilterContext *ctx)
yading@10: {
yading@10:     ScaleContext *scale = ctx->priv;
yading@10:     int ret;
yading@10: 
yading@10:     if (scale->size_str && (scale->w_expr || scale->h_expr)) {
yading@10:         av_log(ctx, AV_LOG_ERROR,
yading@10:                "Size and width/height expressions cannot be set at the same time.\n");
yading@10:             return AVERROR(EINVAL);
yading@10:     }
yading@10: 
yading@10:     if (scale->w_expr && !scale->h_expr)
yading@10:         FFSWAP(char *, scale->w_expr, scale->size_str);
yading@10: 
yading@10:     if (scale->size_str) {
yading@10:         char buf[32];
yading@10:         if ((ret = av_parse_video_size(&scale->w, &scale->h, scale->size_str)) < 0) {
yading@10:             av_log(ctx, AV_LOG_ERROR,
yading@10:                    "Invalid size '%s'\n", scale->size_str);
yading@10:             return ret;
yading@10:         }
yading@10:         snprintf(buf, sizeof(buf)-1, "%d", scale->w);
yading@10:         av_opt_set(scale, "w", buf, 0);
yading@10:         snprintf(buf, sizeof(buf)-1, "%d", scale->h);
yading@10:         av_opt_set(scale, "h", buf, 0);
yading@10:     }
yading@10:     if (!scale->w_expr)
yading@10:         av_opt_set(scale, "w", "iw", 0);
yading@10:     if (!scale->h_expr)
yading@10:         av_opt_set(scale, "h", "ih", 0);
yading@10: 
yading@10:     av_log(ctx, AV_LOG_VERBOSE, "w:%s h:%s flags:'%s' interl:%d\n",
yading@10:            scale->w_expr, scale->h_expr, (char *)av_x_if_null(scale->flags_str, ""), scale->interlaced);
yading@10: 
yading@10:     scale->flags = SWS_BILINEAR;
yading@10: 
yading@10:     if (scale->flags_str) {
yading@10:         const AVClass *class = sws_get_class();
yading@10:         const AVOption    *o = av_opt_find(&class, "sws_flags", NULL, 0,
yading@10:                                            AV_OPT_SEARCH_FAKE_OBJ);
yading@10:         int ret = av_opt_eval_flags(&class, o, scale->flags_str, &scale->flags);
yading@10:         if (ret < 0)
yading@10:             return ret;
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold void uninit(AVFilterContext *ctx)
yading@10: {
yading@10:     ScaleContext *scale = ctx->priv;
yading@10:     sws_freeContext(scale->sws);
yading@10:     sws_freeContext(scale->isws[0]);
yading@10:     sws_freeContext(scale->isws[1]);
yading@10:     scale->sws = NULL;
yading@10:     av_opt_free(scale);
yading@10: }
yading@10: 
yading@10: static int query_formats(AVFilterContext *ctx)
yading@10: {
yading@10:     AVFilterFormats *formats;
yading@10:     enum AVPixelFormat pix_fmt;
yading@10:     int ret;
yading@10: 
yading@10:     if (ctx->inputs[0]) {
yading@10:         formats = NULL;
yading@10:         for (pix_fmt = 0; pix_fmt < AV_PIX_FMT_NB; pix_fmt++)
yading@10:             if (   sws_isSupportedInput(pix_fmt)
yading@10:                 && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
yading@10:                 ff_formats_unref(&formats);
yading@10:                 return ret;
yading@10:             }
yading@10:         ff_formats_ref(formats, &ctx->inputs[0]->out_formats);
yading@10:     }
yading@10:     if (ctx->outputs[0]) {
yading@10:         formats = NULL;
yading@10:         for (pix_fmt = 0; pix_fmt < AV_PIX_FMT_NB; pix_fmt++)
yading@10:             if (   (sws_isSupportedOutput(pix_fmt) || pix_fmt == AV_PIX_FMT_PAL8)
yading@10:                 && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
yading@10:                 ff_formats_unref(&formats);
yading@10:                 return ret;
yading@10:             }
yading@10:         ff_formats_ref(formats, &ctx->outputs[0]->in_formats);
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int config_props(AVFilterLink *outlink)
yading@10: {
yading@10:     AVFilterContext *ctx = outlink->src;
yading@10:     AVFilterLink *inlink = outlink->src->inputs[0];
yading@10:     enum AVPixelFormat outfmt = outlink->format;
yading@10:     ScaleContext *scale = ctx->priv;
yading@10:     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
yading@10:     int64_t w, h;
yading@10:     double var_values[VARS_NB], res;
yading@10:     char *expr;
yading@10:     int ret;
yading@10: 
yading@10:     var_values[VAR_IN_W]  = var_values[VAR_IW] = inlink->w;
yading@10:     var_values[VAR_IN_H]  = var_values[VAR_IH] = inlink->h;
yading@10:     var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
yading@10:     var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
yading@10:     var_values[VAR_A]     = (double) inlink->w / inlink->h;
yading@10:     var_values[VAR_SAR]   = inlink->sample_aspect_ratio.num ?
yading@10:         (double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
yading@10:     var_values[VAR_DAR]   = var_values[VAR_A] * var_values[VAR_SAR];
yading@10:     var_values[VAR_HSUB]  = 1 << desc->log2_chroma_w;
yading@10:     var_values[VAR_VSUB]  = 1 << desc->log2_chroma_h;
yading@10: 
yading@10:     /* evaluate width and height */
yading@10:     av_expr_parse_and_eval(&res, (expr = scale->w_expr),
yading@10:                            var_names, var_values,
yading@10:                            NULL, NULL, NULL, NULL, NULL, 0, ctx);
yading@10:     scale->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
yading@10:     if ((ret = av_expr_parse_and_eval(&res, (expr = scale->h_expr),
yading@10:                                       var_names, var_values,
yading@10:                                       NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
yading@10:         goto fail;
yading@10:     scale->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
yading@10:     /* evaluate again the width, as it may depend on the output height */
yading@10:     if ((ret = av_expr_parse_and_eval(&res, (expr = scale->w_expr),
yading@10:                                       var_names, var_values,
yading@10:                                       NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
yading@10:         goto fail;
yading@10:     scale->w = res;
yading@10: 
yading@10:     w = scale->w;
yading@10:     h = scale->h;
yading@10: 
yading@10:     /* sanity check params */
yading@10:     if (w <  -1 || h <  -1) {
yading@10:         av_log(ctx, AV_LOG_ERROR, "Size values less than -1 are not acceptable.\n");
yading@10:         return AVERROR(EINVAL);
yading@10:     }
yading@10:     if (w == -1 && h == -1)
yading@10:         scale->w = scale->h = 0;
yading@10: 
yading@10:     if (!(w = scale->w))
yading@10:         w = inlink->w;
yading@10:     if (!(h = scale->h))
yading@10:         h = inlink->h;
yading@10:     if (w == -1)
yading@10:         w = av_rescale(h, inlink->w, inlink->h);
yading@10:     if (h == -1)
yading@10:         h = av_rescale(w, inlink->h, inlink->w);
yading@10: 
yading@10:     if (w > INT_MAX || h > INT_MAX ||
yading@10:         (h * inlink->w) > INT_MAX  ||
yading@10:         (w * inlink->h) > INT_MAX)
yading@10:         av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
yading@10: 
yading@10:     outlink->w = w;
yading@10:     outlink->h = h;
yading@10: 
yading@10:     /* TODO: make algorithm configurable */
yading@10: 
yading@10:     scale->input_is_pal = desc->flags & PIX_FMT_PAL ||
yading@10:                           desc->flags & PIX_FMT_PSEUDOPAL;
yading@10:     if (outfmt == AV_PIX_FMT_PAL8) outfmt = AV_PIX_FMT_BGR8;
yading@10:     scale->output_is_pal = av_pix_fmt_desc_get(outfmt)->flags & PIX_FMT_PAL ||
yading@10:                            av_pix_fmt_desc_get(outfmt)->flags & PIX_FMT_PSEUDOPAL;
yading@10: 
yading@10:     if (scale->sws)
yading@10:         sws_freeContext(scale->sws);
yading@10:     if (inlink->w == outlink->w && inlink->h == outlink->h &&
yading@10:         inlink->format == outlink->format)
yading@10:         scale->sws = NULL;
yading@10:     else {
yading@10:         scale->sws = sws_getContext(inlink ->w, inlink ->h, inlink ->format,
yading@10:                                     outlink->w, outlink->h, outfmt,
yading@10:                                     scale->flags, NULL, NULL, NULL);
yading@10:         if (scale->isws[0])
yading@10:             sws_freeContext(scale->isws[0]);
yading@10:         scale->isws[0] = sws_getContext(inlink ->w, inlink ->h/2, inlink ->format,
yading@10:                                         outlink->w, outlink->h/2, outfmt,
yading@10:                                         scale->flags, NULL, NULL, NULL);
yading@10:         if (scale->isws[1])
yading@10:             sws_freeContext(scale->isws[1]);
yading@10:         scale->isws[1] = sws_getContext(inlink ->w, inlink ->h/2, inlink ->format,
yading@10:                                         outlink->w, outlink->h/2, outfmt,
yading@10:                                         scale->flags, NULL, NULL, NULL);
yading@10:         if (!scale->sws || !scale->isws[0] || !scale->isws[1])
yading@10:             return AVERROR(EINVAL);
yading@10:     }
yading@10: 
yading@10:     if (inlink->sample_aspect_ratio.num){
yading@10:         outlink->sample_aspect_ratio = av_mul_q((AVRational){outlink->h * inlink->w, outlink->w * inlink->h}, inlink->sample_aspect_ratio);
yading@10:     } else
yading@10:         outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
yading@10: 
yading@10:     av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d fmt:%s sar:%d/%d -> w:%d h:%d fmt:%s sar:%d/%d flags:0x%0x\n",
yading@10:            inlink ->w, inlink ->h, av_get_pix_fmt_name( inlink->format),
yading@10:            inlink->sample_aspect_ratio.num, inlink->sample_aspect_ratio.den,
yading@10:            outlink->w, outlink->h, av_get_pix_fmt_name(outlink->format),
yading@10:            outlink->sample_aspect_ratio.num, outlink->sample_aspect_ratio.den,
yading@10:            scale->flags);
yading@10:     return 0;
yading@10: 
yading@10: fail:
yading@10:     av_log(NULL, AV_LOG_ERROR,
yading@10:            "Error when evaluating the expression '%s'.\n"
yading@10:            "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
yading@10:            expr, scale->w_expr, scale->h_expr);
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: static int scale_slice(AVFilterLink *link, AVFrame *out_buf, AVFrame *cur_pic, struct SwsContext *sws, int y, int h, int mul, int field)
yading@10: {
yading@10:     ScaleContext *scale = link->dst->priv;
yading@10:     const uint8_t *in[4];
yading@10:     uint8_t *out[4];
yading@10:     int in_stride[4],out_stride[4];
yading@10:     int i;
yading@10: 
yading@10:     for(i=0; i<4; i++){
yading@10:         int vsub= ((i+1)&2) ? scale->vsub : 0;
yading@10:          in_stride[i] = cur_pic->linesize[i] * mul;
yading@10:         out_stride[i] = out_buf->linesize[i] * mul;
yading@10:          in[i] = cur_pic->data[i] + ((y>>vsub)+field) * cur_pic->linesize[i];
yading@10:         out[i] = out_buf->data[i] +            field  * out_buf->linesize[i];
yading@10:     }
yading@10:     if(scale->input_is_pal)
yading@10:          in[1] = cur_pic->data[1];
yading@10:     if(scale->output_is_pal)
yading@10:         out[1] = out_buf->data[1];
yading@10: 
yading@10:     return sws_scale(sws, in, in_stride, y/mul, h,
yading@10:                          out,out_stride);
yading@10: }
yading@10: 
yading@10: static int filter_frame(AVFilterLink *link, AVFrame *in)
yading@10: {
yading@10:     ScaleContext *scale = link->dst->priv;
yading@10:     AVFilterLink *outlink = link->dst->outputs[0];
yading@10:     AVFrame *out;
yading@10:     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
yading@10:     char buf[32];
yading@10: 
yading@10:     if(   in->width  != link->w
yading@10:        || in->height != link->h
yading@10:        || in->format != link->format) {
yading@10:         int ret;
yading@10:         snprintf(buf, sizeof(buf)-1, "%d", outlink->w);
yading@10:         av_opt_set(scale, "w", buf, 0);
yading@10:         snprintf(buf, sizeof(buf)-1, "%d", outlink->h);
yading@10:         av_opt_set(scale, "h", buf, 0);
yading@10: 
yading@10:         link->dst->inputs[0]->format = in->format;
yading@10:         link->dst->inputs[0]->w      = in->width;
yading@10:         link->dst->inputs[0]->h      = in->height;
yading@10: 
yading@10:         if ((ret = config_props(outlink)) < 0)
yading@10:             return ret;
yading@10:     }
yading@10: 
yading@10:     if (!scale->sws)
yading@10:         return ff_filter_frame(outlink, in);
yading@10: 
yading@10:     scale->hsub = desc->log2_chroma_w;
yading@10:     scale->vsub = desc->log2_chroma_h;
yading@10: 
yading@10:     out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
yading@10:     if (!out) {
yading@10:         av_frame_free(&in);
yading@10:         return AVERROR(ENOMEM);
yading@10:     }
yading@10: 
yading@10:     av_frame_copy_props(out, in);
yading@10:     out->width  = outlink->w;
yading@10:     out->height = outlink->h;
yading@10: 
yading@10:     if(scale->output_is_pal)
yading@10:         avpriv_set_systematic_pal2((uint32_t*)out->data[1], outlink->format == AV_PIX_FMT_PAL8 ? AV_PIX_FMT_BGR8 : outlink->format);
yading@10: 
yading@10:     av_reduce(&out->sample_aspect_ratio.num, &out->sample_aspect_ratio.den,
yading@10:               (int64_t)in->sample_aspect_ratio.num * outlink->h * link->w,
yading@10:               (int64_t)in->sample_aspect_ratio.den * outlink->w * link->h,
yading@10:               INT_MAX);
yading@10: 
yading@10:     if(scale->interlaced>0 || (scale->interlaced<0 && in->interlaced_frame)){
yading@10:         scale_slice(link, out, in, scale->isws[0], 0, (link->h+1)/2, 2, 0);
yading@10:         scale_slice(link, out, in, scale->isws[1], 0,  link->h   /2, 2, 1);
yading@10:     }else{
yading@10:         scale_slice(link, out, in, scale->sws, 0, link->h, 1, 0);
yading@10:     }
yading@10: 
yading@10:     av_frame_free(&in);
yading@10:     return ff_filter_frame(outlink, out);
yading@10: }
yading@10: 
yading@10: #define OFFSET(x) offsetof(ScaleContext, x)
yading@10: #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
yading@10: 
yading@10: static const AVOption scale_options[] = {
yading@10:     { "w",     "Output video width",          OFFSET(w_expr),    AV_OPT_TYPE_STRING,        .flags = FLAGS },
yading@10:     { "width", "Output video width",          OFFSET(w_expr),    AV_OPT_TYPE_STRING,        .flags = FLAGS },
yading@10:     { "h",     "Output video height",         OFFSET(h_expr),    AV_OPT_TYPE_STRING,        .flags = FLAGS },
yading@10:     { "height","Output video height",         OFFSET(h_expr),    AV_OPT_TYPE_STRING,        .flags = FLAGS },
yading@10:     { "flags", "Flags to pass to libswscale", OFFSET(flags_str), AV_OPT_TYPE_STRING, { .str = "bilinear" }, .flags = FLAGS },
yading@10:     { "interl", "set interlacing", OFFSET(interlaced), AV_OPT_TYPE_INT, {.i64 = 0 }, -1, 1, FLAGS },
yading@10:     { "size",   "set video size",          OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
yading@10:     { "s",      "set video size",          OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
yading@10:     { NULL },
yading@10: };
yading@10: 
yading@10: AVFILTER_DEFINE_CLASS(scale);
yading@10: 
yading@10: static const AVFilterPad avfilter_vf_scale_inputs[] = {
yading@10:     {
yading@10:         .name        = "default",
yading@10:         .type        = AVMEDIA_TYPE_VIDEO,
yading@10:         .filter_frame = filter_frame,
yading@10:     },
yading@10:     { NULL }
yading@10: };
yading@10: 
yading@10: static const AVFilterPad avfilter_vf_scale_outputs[] = {
yading@10:     {
yading@10:         .name         = "default",
yading@10:         .type         = AVMEDIA_TYPE_VIDEO,
yading@10:         .config_props = config_props,
yading@10:     },
yading@10:     { NULL }
yading@10: };
yading@10: 
yading@10: AVFilter avfilter_vf_scale = {
yading@10:     .name      = "scale",
yading@10:     .description = NULL_IF_CONFIG_SMALL("Scale the input video to width:height size and/or convert the image format."),
yading@10: 
yading@10:     .init      = init,
yading@10:     .uninit    = uninit,
yading@10: 
yading@10:     .query_formats = query_formats,
yading@10: 
yading@10:     .priv_size = sizeof(ScaleContext),
yading@10:     .priv_class = &scale_class,
yading@10: 
yading@10:     .inputs    = avfilter_vf_scale_inputs,
yading@10:     .outputs   = avfilter_vf_scale_outputs,
yading@10: };