From 75b67a8a99202321e9241e29c98c633a1b20846b Mon Sep 17 00:00:00 2001 From: Stefano Sabatini Date: Sat, 25 Sep 2010 01:18:43 +0000 Subject: [PATCH] Make the crop filters accept parametric expressions. Originally committed as revision 25185 to svn://svn.ffmpeg.org/ffmpeg/trunk --- Changelog | 1 + doc/filters.texi | 117 +++++++++++++++++++------ libavfilter/avfilter.h | 2 +- libavfilter/vf_crop.c | 178 ++++++++++++++++++++++++++++++++++---- tests/lavfi-regression.sh | 10 +-- 5 files changed, 258 insertions(+), 50 deletions(-) diff --git a/Changelog b/Changelog index c29d15ac7d..04c6800b7c 100644 --- a/Changelog +++ b/Changelog @@ -38,6 +38,7 @@ version : - ocv_smooth filter - frei0r wrapper filter - change crop filter syntax to width:height:x:y +- make the crop filter accept parametric expressions version 0.6: diff --git a/doc/filters.texi b/doc/filters.texi index f934082d9a..1dc222a119 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -26,35 +26,102 @@ Below is a description of the currently available video filters. @section crop -Crop the input video to @var{width}:@var{height}:@var{x}:@var{y}. +Crop the input video to @var{out_w}:@var{out_h}:@var{x}:@var{y}. +The parameters are expressions containing the following constants: + +@table @option +@item E, PI, PHI +the corresponding mathematical approximated values for e +(euler number), pi (greek PI), PHI (golden ratio) + +@item x, y +the computed values for @var{x} and @var{y}. They are evaluated for +each new frame. + +@item in_w, in_h +the input width and heigth + +@item iw, ih +same as @var{in_w} and @var{in_h} + +@item out_w, out_h +the output (cropped) width and heigth + +@item ow, oh +same as @var{out_w} and @var{out_h} + +@item n +the number of input frame, starting from 0 + +@item pos +the position in the file of the input frame, NAN if unknown + +@item t +timestamp expressed in seconds, NAN if the input timestamp is unknown + +@end table + +The @var{out_w} and @var{out_h} parameters specify the expressions for +the width and height of the output (cropped) video. They are +evaluated just at the configuration of the filter. + +The default value of @var{out_w} is "in_w", and the default value of +@var{out_h} is "in_h". + +The expression for @var{out_w} may depend on the value of @var{out_h}, +and the expression for @var{out_h} may depend on @var{out_w}, but they +cannot depend on @var{x} and @var{y}, as @var{x} and @var{y} are +evaluated after @var{out_w} and @var{out_h}. + +The @var{x} and @var{y} parameters specify the expressions for the +position of the top-left corner of the output (non-cropped) area. They +are evaluated for each frame. If the evaluated value is not valid, it +is approximated to the nearest valid value. + +The default value of @var{x} is "(in_w-out_w)/2", and the default +value for @var{y} is "(in_h-out_h)/2", which set the cropped area at +the center of the input image. + +The expression for @var{x} may depend on @var{y}, and the expression +for @var{y} may depend on @var{x}. + +Follow some examples: @example -./ffmpeg -i in.avi -vf "crop=0:240:0:0" out.avi +# crop the central input area with size 100x100 +crop=100:100 + +# crop the central input area with size 2/3 of the input video +"crop=2/3*in_w:2/3*in_h" + +# crop the input video central square +crop=in_h + +# delimit the rectangle with the top-left corner placed at position +# 100:100 and the right-bottom corner corresponding to the right-bottom +# corner of the input image. +crop=in_w-100:in_h-100:100:100 + +# crop 10 pixels from the lefth and right borders, and 20 pixels from +# the top and bottom borders +"crop=in_w-2*10:in_h-2*20" + +# keep only the bottom right quarter of the input image +"crop=in_w/2:in_h/2:in_w/2:in_h/2" + +# crop height for getting Greek harmony +"crop=in_w:1/PHI*in_w" + +# trembling effect +"crop=in_w/2:in_h/2:(in_w-out_w)/2+((in_w-out_w)/2)*sin(n/10):(in_h-out_h)/2 +((in_h-out_h)/2)*sin(n/7)" + +# erratic camera effect depending on timestamp and position +"crop=in_w/2:in_h/2:(in_w-out_w)/2+((in_w-out_w)/2)*sin(t*10):(in_h-out_h)/2 +((in_h-out_h)/2)*sin(t*13)" + +# set x depending on the value of y +"crop=in_w/2:in_h/2:y:10+10*sin(n/10)" @end example -The @var{width} and @var{height} parameters specify the width and height -of the output (non-cropped) area. - -A value of 0 is interpreted as the maximum possible size contained in -the area delimited by the top-left corner at position x:y. - -@var{x} and @var{y} specify the position of the top-left corner of the -output (non-cropped) area. - -The default value of @var{x} and @var{y} is 0. - -For example the parameters: - -@example -"crop=0:0:100:100" -@end example - -will delimit the rectangle with the top-left corner placed at position -100:100 and the right-bottom corner corresponding to the right-bottom -corner of the input image. - -The default value of @var{width} and @var{height} is 0. - @section fifo Buffer input images and send them when they are requested. diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h index 6fe6fa16ff..39e5bc942a 100644 --- a/libavfilter/avfilter.h +++ b/libavfilter/avfilter.h @@ -25,7 +25,7 @@ #include "libavutil/avutil.h" #define LIBAVFILTER_VERSION_MAJOR 1 -#define LIBAVFILTER_VERSION_MINOR 41 +#define LIBAVFILTER_VERSION_MINOR 42 #define LIBAVFILTER_VERSION_MICRO 0 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \ diff --git a/libavfilter/vf_crop.c b/libavfilter/vf_crop.c index dfbc223483..d190d725cc 100644 --- a/libavfilter/vf_crop.c +++ b/libavfilter/vf_crop.c @@ -24,8 +24,43 @@ */ #include "avfilter.h" +#include "libavutil/eval.h" +#include "libavutil/avstring.h" +#include "libavutil/libm.h" #include "libavcore/imgutils.h" +static const char *var_names[] = { + "E", + "PHI", + "PI", + "in_w", "iw", ///< width of the input video + "in_h", "ih", ///< height of the input video + "out_w", "ow", ///< width of the cropped video + "out_h", "oh", ///< height of the cropped video + "x", + "y", + "n", ///< number of frame + "pos", ///< position in the file + "t", ///< timestamp expressed in seconds + NULL +}; + +enum var_name { + E, + PHI, + PI, + IN_W, IW, + IN_H, IH, + OUT_W, OW, + OUT_H, OH, + X, + Y, + N, + POS, + T, + VARS_NB +}; + typedef struct { int x; ///< x offset of the non-cropped area with respect to the input area int y; ///< y offset of the non-cropped area with respect to the input area @@ -34,6 +69,9 @@ typedef struct { int max_step[4]; ///< max pixel step for each plane, expressed as a number of bytes int hsub, vsub; ///< chroma subsampling + char x_expr[256], y_expr[256], ow_expr[256], oh_expr[256]; + AVExpr *x_pexpr, *y_pexpr; /* parsed expressions for x and y */ + double var_values[VARS_NB]; } CropContext; static int query_formats(AVFilterContext *ctx) @@ -72,44 +110,114 @@ static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque) { CropContext *crop = ctx->priv; + av_strlcpy(crop->ow_expr, "iw", sizeof(crop->ow_expr)); + av_strlcpy(crop->oh_expr, "ih", sizeof(crop->oh_expr)); + av_strlcpy(crop->x_expr, "(in_w-out_w)/2", sizeof(crop->x_expr)); + av_strlcpy(crop->y_expr, "(in_h-out_h)/2", sizeof(crop->y_expr)); + if (args) - sscanf(args, "%d:%d:%d:%d", &crop->w, &crop->h, &crop->x, &crop->y); + sscanf(args, "%255[^:]:%255[^:]:%255[^:]:%255[^:]", crop->ow_expr, crop->oh_expr, crop->x_expr, crop->y_expr); return 0; } +static av_cold void uninit(AVFilterContext *ctx) +{ + CropContext *crop = ctx->priv; + + av_free_expr(crop->x_pexpr); crop->x_pexpr = NULL; + av_free_expr(crop->y_pexpr); crop->y_pexpr = NULL; +} + +static inline int normalize_double(int *n, double d) +{ + int ret = 0; + + if (isnan(d)) { + ret = AVERROR(EINVAL); + } else if (d > INT_MAX || d < INT_MIN) { + *n = d > INT_MAX ? INT_MAX : INT_MIN; + ret = AVERROR(EINVAL); + } else + *n = round(d); + + return ret; +} + static int config_input(AVFilterLink *link) { AVFilterContext *ctx = link->dst; CropContext *crop = ctx->priv; const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[link->format]; + int ret; + const char *expr; + double res; + + crop->var_values[E] = M_E; + crop->var_values[PHI] = M_PHI; + crop->var_values[PI] = M_PI; + crop->var_values[IN_W] = crop->var_values[IW] = ctx->inputs[0]->w; + crop->var_values[IN_H] = crop->var_values[IH] = ctx->inputs[0]->h; + crop->var_values[X] = NAN; + crop->var_values[Y] = NAN; + crop->var_values[OUT_W] = crop->var_values[OW] = NAN; + crop->var_values[OUT_H] = crop->var_values[OH] = NAN; + crop->var_values[N] = 0; + crop->var_values[T] = NAN; + crop->var_values[POS] = NAN; av_image_fill_max_pixsteps(crop->max_step, NULL, pix_desc); crop->hsub = av_pix_fmt_descriptors[link->format].log2_chroma_w; crop->vsub = av_pix_fmt_descriptors[link->format].log2_chroma_h; - if (crop->w == 0) - crop->w = link->w - crop->x; - if (crop->h == 0) - crop->h = link->h - crop->y; - - crop->x &= ~((1 << crop->hsub) - 1); - crop->y &= ~((1 << crop->vsub) - 1); - - av_log(link->dst, AV_LOG_INFO, "w:%d h:%d x:%d y:%d\n", - crop->w, crop->h, crop->x, crop->y); - - if (crop->x < 0 || crop->y < 0 || - crop->w <= 0 || crop->h <= 0 || - (unsigned)crop->x + (unsigned)crop->w > link->w || - (unsigned)crop->y + (unsigned)crop->h > link->h) { + if ((ret = av_parse_and_eval_expr(&res, (expr = crop->ow_expr), + var_names, crop->var_values, + NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr; + crop->var_values[OUT_W] = crop->var_values[OW] = res; + if ((ret = av_parse_and_eval_expr(&res, (expr = crop->oh_expr), + var_names, crop->var_values, + NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr; + crop->var_values[OUT_H] = crop->var_values[OH] = res; + /* evaluate again ow as it may depend on oh */ + if ((ret = av_parse_and_eval_expr(&res, (expr = crop->ow_expr), + var_names, crop->var_values, + NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0) goto fail_expr; + crop->var_values[OUT_W] = crop->var_values[OW] = res; + if (normalize_double(&crop->w, crop->var_values[OUT_W]) < 0 || + normalize_double(&crop->h, crop->var_values[OUT_H]) < 0) { av_log(ctx, AV_LOG_ERROR, - "Output area %d:%d:%d:%d not within the input area 0:0:%d:%d or zero-sized\n", - crop->x, crop->y, crop->w, crop->h, link->w, link->h); + "Too big value or invalid expression for out_w/ow or out_h/oh. " + "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n", + crop->ow_expr, crop->oh_expr); + return AVERROR(EINVAL); + } + crop->w &= ~((1 << crop->hsub) - 1); + crop->h &= ~((1 << crop->vsub) - 1); + + if ((ret = av_parse_expr(&crop->x_pexpr, crop->x_expr, var_names, + NULL, NULL, NULL, NULL, 0, ctx)) < 0 || + (ret = av_parse_expr(&crop->y_pexpr, crop->y_expr, var_names, + NULL, NULL, NULL, NULL, 0, ctx)) < 0) + return AVERROR(EINVAL); + + if (crop->w <= 0 || crop->h <= 0 || + crop->w > link->w || crop->h > link->h) { + av_log(ctx, AV_LOG_ERROR, + "Invalid too big or non positive size for width '%d' or height '%d'\n", + crop->w, crop->h); return AVERROR(EINVAL); } + /* set default, required in the case the first computed value for x/y is NAN */ + crop->x = (link->w - crop->w) / 2; + crop->y = (link->h - crop->h) / 2; + crop->x &= ~((1 << crop->hsub) - 1); + crop->y &= ~((1 << crop->vsub) - 1); return 0; + +fail_expr: + av_log(NULL, AV_LOG_ERROR, "Error when evaluating the expression '%s'\n", expr); + return ret; } static int config_output(AVFilterLink *link) @@ -124,13 +232,35 @@ static int config_output(AVFilterLink *link) static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref) { - CropContext *crop = link->dst->priv; + AVFilterContext *ctx = link->dst; + CropContext *crop = ctx->priv; AVFilterBufferRef *ref2 = avfilter_ref_buffer(picref, ~0); int i; picref->video->w = crop->w; picref->video->h = crop->h; + /* FIXME: when the TB will be settable */ + crop->var_values[T] = picref->pts == AV_NOPTS_VALUE ? NAN : (double)picref->pts / AV_TIME_BASE; + crop->var_values[POS] = picref->pos == -1 ? NAN : picref->pos; + crop->var_values[X] = av_eval_expr(crop->x_pexpr, crop->var_values, NULL); + crop->var_values[Y] = av_eval_expr(crop->y_pexpr, crop->var_values, NULL); + crop->var_values[X] = av_eval_expr(crop->x_pexpr, crop->var_values, NULL); + + normalize_double(&crop->x, crop->var_values[X]); + normalize_double(&crop->y, crop->var_values[Y]); + + if (crop->x < 0) crop->x = 0; + if (crop->y < 0) crop->y = 0; + if ((unsigned)crop->x + (unsigned)crop->w > link->w) crop->x = link->w - crop->w; + if ((unsigned)crop->y + (unsigned)crop->h > link->h) crop->y = link->h - crop->h; + crop->x &= ~((1 << crop->hsub) - 1); + crop->y &= ~((1 << crop->vsub) - 1); + + av_log(ctx, AV_LOG_DEBUG, + "n:%d t:%f x:%d y:%d x+w:%d y+h:%d\n", + (int)crop->var_values[N], crop->var_values[T], crop->x, crop->y, crop->x+crop->w, crop->y+crop->h); + ref2->data[0] += crop->y * ref2->linesize[0]; ref2->data[0] += crop->x * crop->max_step[0]; @@ -170,6 +300,14 @@ static void draw_slice(AVFilterLink *link, int y, int h, int slice_dir) avfilter_draw_slice(ctx->outputs[0], y - crop->y, h, slice_dir); } +static void end_frame(AVFilterLink *link) +{ + CropContext *crop = link->dst->priv; + + crop->var_values[N] += 1.0; + avfilter_end_frame(link->dst->outputs[0]); +} + AVFilter avfilter_vf_crop = { .name = "crop", .description = NULL_IF_CONFIG_SMALL("Crop the input video to width:height:x:y."), @@ -178,11 +316,13 @@ AVFilter avfilter_vf_crop = { .query_formats = query_formats, .init = init, + .uninit = uninit, .inputs = (AVFilterPad[]) {{ .name = "default", .type = AVMEDIA_TYPE_VIDEO, .start_frame = start_frame, .draw_slice = draw_slice, + .end_frame = end_frame, .get_video_buffer = avfilter_null_get_video_buffer, .config_props = config_input, }, { .name = NULL}}, diff --git a/tests/lavfi-regression.sh b/tests/lavfi-regression.sh index 112dda880a..a3e75dd6c8 100755 --- a/tests/lavfi-regression.sh +++ b/tests/lavfi-regression.sh @@ -22,15 +22,15 @@ do_lavfi() { fi } -do_lavfi "crop" "crop=0:0:100:100" -do_lavfi "crop_scale" "crop=0:0:100:100,scale=400:-1" -do_lavfi "crop_scale_vflip" "null,null,crop=0:0:200:200,crop=0:0:20:20,scale=200:200,scale=250:250,vflip,vflip,null,scale=200:200,crop=0:0:100:100,vflip,scale=200:200,null,vflip,crop=0:0:100:100,null" -do_lavfi "crop_vflip" "crop=0:0:100:100,vflip" +do_lavfi "crop" "crop=iw-100:ih-100:100:100" +do_lavfi "crop_scale" "crop=iw-100:ih-100:100:100,scale=400:-1" +do_lavfi "crop_scale_vflip" "null,null,crop=iw-200:ih-200:200:200,crop=iw-20:ih-20:20:20,scale=200:200,scale=250:250,vflip,vflip,null,scale=200:200,crop=iw-100:ih-100:100:100,vflip,scale=200:200,null,vflip,crop=iw-100:ih-100:100:100,null" +do_lavfi "crop_vflip" "crop=iw-100:ih-100:100:100,vflip" do_lavfi "null" "null" do_lavfi "scale200" "scale=200:200" do_lavfi "scale500" "scale=500:500" do_lavfi "vflip" "vflip" -do_lavfi "vflip_crop" "vflip,crop=0:0:100:100" +do_lavfi "vflip_crop" "vflip,crop=iw-100:ih-100:100:100" do_lavfi "vflip_vflip" "vflip,vflip" do_lavfi_pixfmts(){