From 75b67a8a99202321e9241e29c98c633a1b20846b Mon Sep 17 00:00:00 2001 From: Stefano Sabatini Date: Sat, 25 Sep 2010 01:18:43 +0000 Subject: Make the crop filters accept parametric expressions. Originally committed as revision 25185 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavfilter/vf_crop.c | 174 +++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 157 insertions(+), 17 deletions(-) (limited to 'libavfilter/vf_crop.c') 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); + 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, + "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); - 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 ((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->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 (crop->w <= 0 || crop->h <= 0 || + crop->w > link->w || crop->h > link->h) { 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); + "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}}, -- cgit v1.2.3