diff options
Diffstat (limited to 'libavfilter/vf_overlay.c')
-rw-r--r-- | libavfilter/vf_overlay.c | 225 |
1 files changed, 186 insertions, 39 deletions
diff --git a/libavfilter/vf_overlay.c b/libavfilter/vf_overlay.c index 39b2375..6fa10ae 100644 --- a/libavfilter/vf_overlay.c +++ b/libavfilter/vf_overlay.c @@ -3,20 +3,20 @@ * Copyright (c) 2010 Baptiste Coudurier * Copyright (c) 2007 Bobby Bingham * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * 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. * - * Libav is distributed in the hope that it will be useful, + * 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 Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -28,15 +28,14 @@ #include "avfilter.h" #include "libavutil/eval.h" #include "libavutil/avstring.h" +#include "libavutil/opt.h" #include "libavutil/pixdesc.h" #include "libavutil/imgutils.h" #include "libavutil/mathematics.h" #include "internal.h" +#include "drawutils.h" static const char *var_names[] = { - "E", - "PHI", - "PI", "main_w", "W", ///< width of the main video "main_h", "H", ///< height of the main video "overlay_w", "w", ///< width of the overlay video @@ -45,9 +44,6 @@ static const char *var_names[] = { }; enum var_name { - VAR_E, - VAR_PHI, - VAR_PI, VAR_MAIN_W, VAR_MW, VAR_MAIN_H, VAR_MH, VAR_OVERLAY_W, VAR_OW, @@ -58,61 +54,153 @@ enum var_name { #define MAIN 0 #define OVERLAY 1 +#define R 0 +#define G 1 +#define B 2 +#define A 3 + +#define Y 0 +#define U 1 +#define V 2 + typedef struct { + const AVClass *class; int x, y; ///< position of overlayed picture + int allow_packed_rgb; + uint8_t main_is_packed_rgb; + uint8_t main_rgba_map[4]; + uint8_t main_has_alpha; + uint8_t overlay_is_packed_rgb; + uint8_t overlay_rgba_map[4]; + uint8_t overlay_has_alpha; + AVFilterBufferRef *overpicref; - int max_plane_step[4]; ///< steps per pixel for each plane + int main_pix_step[4]; ///< steps per pixel for each plane of the main output + int overlay_pix_step[4]; ///< steps per pixel for each plane of the overlay int hsub, vsub; ///< chroma subsampling values - char x_expr[256], y_expr[256]; + char *x_expr, *y_expr; } OverlayContext; +#define OFFSET(x) offsetof(OverlayContext, x) + +static const AVOption overlay_options[] = { + { "x", "set the x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX }, + { "y", "set the y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX }, + {"rgb", "force packed RGB in input and output", OFFSET(allow_packed_rgb), AV_OPT_TYPE_INT, {.dbl=0}, 0, 1 }, + {NULL}, +}; + +static const char *overlay_get_name(void *ctx) +{ + return "overlay"; +} + +static const AVClass overlay_class = { + "OverlayContext", + overlay_get_name, + overlay_options +}; + static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque) { OverlayContext *over = ctx->priv; + char *args1 = av_strdup(args); + char *expr, *bufptr = NULL; + int ret = 0; - av_strlcpy(over->x_expr, "0", sizeof(over->x_expr)); - av_strlcpy(over->y_expr, "0", sizeof(over->y_expr)); + over->class = &overlay_class; + av_opt_set_defaults(over); - if (args) - sscanf(args, "%255[^:]:%255[^:]", over->x_expr, over->y_expr); + if (expr = av_strtok(args1, ":", &bufptr)) { + if (!(over->x_expr = av_strdup(expr))) { + ret = AVERROR(ENOMEM); + goto end; + } + } + if (expr = av_strtok(NULL, ":", &bufptr)) { + if (!(over->y_expr = av_strdup(expr))) { + ret = AVERROR(ENOMEM); + goto end; + } + } - return 0; + if (bufptr && (ret = av_set_options_string(over, bufptr, "=", ":")) < 0) + goto end; + +end: + av_free(args1); + return ret; } static av_cold void uninit(AVFilterContext *ctx) { OverlayContext *over = ctx->priv; + av_freep(&over->x_expr); + av_freep(&over->y_expr); + if (over->overpicref) avfilter_unref_buffer(over->overpicref); } static int query_formats(AVFilterContext *ctx) { - const enum PixelFormat inout_pix_fmts[] = { PIX_FMT_YUV420P, PIX_FMT_NONE }; - const enum PixelFormat blend_pix_fmts[] = { PIX_FMT_YUVA420P, PIX_FMT_NONE }; - AVFilterFormats *inout_formats = avfilter_make_format_list(inout_pix_fmts); - AVFilterFormats *blend_formats = avfilter_make_format_list(blend_pix_fmts); + OverlayContext *over = ctx->priv; + + /* overlay formats contains alpha, for avoiding conversion with alpha information loss */ + const enum PixelFormat main_pix_fmts_yuv[] = { PIX_FMT_YUV420P, PIX_FMT_NONE }; + const enum PixelFormat overlay_pix_fmts_yuv[] = { PIX_FMT_YUVA420P, PIX_FMT_NONE }; + const enum PixelFormat main_pix_fmts_rgb[] = { + PIX_FMT_ARGB, PIX_FMT_RGBA, + PIX_FMT_ABGR, PIX_FMT_BGRA, + PIX_FMT_RGB24, PIX_FMT_BGR24, + PIX_FMT_NONE + }; + const enum PixelFormat overlay_pix_fmts_rgb[] = { + PIX_FMT_ARGB, PIX_FMT_RGBA, + PIX_FMT_ABGR, PIX_FMT_BGRA, + PIX_FMT_NONE + }; + + AVFilterFormats *main_formats; + AVFilterFormats *overlay_formats; + + if (over->allow_packed_rgb) { + main_formats = avfilter_make_format_list(main_pix_fmts_rgb); + overlay_formats = avfilter_make_format_list(overlay_pix_fmts_rgb); + } else { + main_formats = avfilter_make_format_list(main_pix_fmts_yuv); + overlay_formats = avfilter_make_format_list(overlay_pix_fmts_yuv); + } - avfilter_formats_ref(inout_formats, &ctx->inputs [MAIN ]->out_formats); - avfilter_formats_ref(blend_formats, &ctx->inputs [OVERLAY]->out_formats); - avfilter_formats_ref(inout_formats, &ctx->outputs[MAIN ]->in_formats ); + avfilter_formats_ref(main_formats, &ctx->inputs [MAIN ]->out_formats); + avfilter_formats_ref(overlay_formats, &ctx->inputs [OVERLAY]->out_formats); + avfilter_formats_ref(main_formats, &ctx->outputs[MAIN ]->in_formats ); return 0; } +static enum PixelFormat alpha_pix_fmts[] = { + PIX_FMT_YUVA420P, PIX_FMT_ARGB, PIX_FMT_ABGR, PIX_FMT_RGBA, + PIX_FMT_BGRA, PIX_FMT_NONE +}; + static int config_input_main(AVFilterLink *inlink) { OverlayContext *over = inlink->dst->priv; const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format]; - av_image_fill_max_pixsteps(over->max_plane_step, NULL, pix_desc); + av_image_fill_max_pixsteps(over->main_pix_step, NULL, pix_desc); + over->hsub = pix_desc->log2_chroma_w; over->vsub = pix_desc->log2_chroma_h; + over->main_is_packed_rgb = + ff_fill_rgba_map(over->main_rgba_map, inlink->format) >= 0; + over->main_has_alpha = ff_fmt_is_in(inlink->format, alpha_pix_fmts); return 0; } @@ -123,13 +211,12 @@ static int config_input_overlay(AVFilterLink *inlink) char *expr; double var_values[VAR_VARS_NB], res; int ret; + const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format]; + + av_image_fill_max_pixsteps(over->overlay_pix_step, NULL, pix_desc); /* Finish the configuration by evaluating the expressions now when both inputs are configured. */ - var_values[VAR_E ] = M_E; - var_values[VAR_PHI] = M_PHI; - var_values[VAR_PI ] = M_PI; - var_values[VAR_MAIN_W ] = var_values[VAR_MW] = ctx->inputs[MAIN ]->w; var_values[VAR_MAIN_H ] = var_values[VAR_MH] = ctx->inputs[MAIN ]->h; var_values[VAR_OVERLAY_W] = var_values[VAR_OW] = ctx->inputs[OVERLAY]->w; @@ -149,6 +236,10 @@ static int config_input_overlay(AVFilterLink *inlink) goto fail; over->x = res; + over->overlay_is_packed_rgb = + ff_fill_rgba_map(over->overlay_rgba_map, inlink->format) >= 0; + over->overlay_has_alpha = ff_fmt_is_in(inlink->format, alpha_pix_fmts); + av_log(ctx, AV_LOG_INFO, "main w:%d h:%d fmt:%s overlay x:%d y:%d w:%d h:%d fmt:%s\n", ctx->inputs[MAIN]->w, ctx->inputs[MAIN]->h, @@ -240,6 +331,10 @@ static void start_frame_overlay(AVFilterLink *inlink, AVFilterBufferRef *inpicre ctx->outputs[0]->time_base); } +// divide by 255 and round to nearest +// apply a fast variant: (X+127)/255 = ((X+127)*257+257)>>16 = ((X+128)*257)>>16 +#define FAST_DIV255(x) ((((x) + 128) * 257) >> 16) + static void blend_slice(AVFilterContext *ctx, AVFilterBufferRef *dst, AVFilterBufferRef *src, int x, int y, int w, int h, @@ -257,21 +352,72 @@ static void blend_slice(AVFilterContext *ctx, start_y = FFMAX(y, slice_y); height = end_y - start_y; - if (dst->format == PIX_FMT_BGR24 || dst->format == PIX_FMT_RGB24) { - uint8_t *dp = dst->data[0] + x * 3 + start_y * dst->linesize[0]; + if (over->main_is_packed_rgb) { + uint8_t *dp = dst->data[0] + x * over->main_pix_step[0] + + start_y * dst->linesize[0]; uint8_t *sp = src->data[0]; - int b = dst->format == PIX_FMT_BGR24 ? 2 : 0; - int r = dst->format == PIX_FMT_BGR24 ? 0 : 2; + uint8_t alpha; ///< the amount of overlay to blend on to main + const int dr = over->main_rgba_map[R]; + const int dg = over->main_rgba_map[G]; + const int db = over->main_rgba_map[B]; + const int da = over->main_rgba_map[A]; + const int dstep = over->main_pix_step[0]; + const int sr = over->overlay_rgba_map[R]; + const int sg = over->overlay_rgba_map[G]; + const int sb = over->overlay_rgba_map[B]; + const int sa = over->overlay_rgba_map[A]; + const int sstep = over->overlay_pix_step[0]; + const int main_has_alpha = over->main_has_alpha; if (slice_y > y) sp += (slice_y - y) * src->linesize[0]; for (i = 0; i < height; i++) { uint8_t *d = dp, *s = sp; for (j = 0; j < width; j++) { - d[r] = (d[r] * (0xff - s[3]) + s[0] * s[3] + 128) >> 8; - d[1] = (d[1] * (0xff - s[3]) + s[1] * s[3] + 128) >> 8; - d[b] = (d[b] * (0xff - s[3]) + s[2] * s[3] + 128) >> 8; - d += 3; - s += 4; + alpha = s[sa]; + + // if the main channel has an alpha channel, alpha has to be calculated + // to create an un-premultiplied (straight) alpha value + if (main_has_alpha && alpha != 0 && alpha != 255) { + // apply the general equation: + // alpha = alpha_overlay / ( (alpha_main + alpha_overlay) - (alpha_main * alpha_overlay) ) + alpha = + // the next line is a faster version of: 255 * 255 * alpha + ( (alpha << 16) - (alpha << 9) + alpha ) + / + // the next line is a faster version of: 255 * (alpha + d[da]) + ( ((alpha + d[da]) << 8 ) - (alpha + d[da]) + - d[da] * alpha ); + } + + switch (alpha) { + case 0: + break; + case 255: + d[dr] = s[sr]; + d[dg] = s[sg]; + d[db] = s[sb]; + break; + default: + // main_value = main_value * (1 - alpha) + overlay_value * alpha + // since alpha is in the range 0-255, the result must divided by 255 + d[dr] = FAST_DIV255(d[dr] * (255 - alpha) + s[sr] * alpha); + d[dg] = FAST_DIV255(d[dg] * (255 - alpha) + s[sg] * alpha); + d[db] = FAST_DIV255(d[db] * (255 - alpha) + s[sb] * alpha); + } + if (main_has_alpha) { + switch (alpha) { + case 0: + break; + case 255: + d[da] = s[sa]; + break; + default: + // apply alpha compositing: main_alpha += (1-main_alpha) * overlay_alpha + d[da] += FAST_DIV255((255 - d[da]) * s[sa]); + } + } + d += dstep; + s += sstep; } dp += dst->linesize[0]; sp += src->linesize[0]; @@ -306,7 +452,8 @@ static void blend_slice(AVFilterContext *ctx, alpha = (alpha_v + alpha_h) >> 1; } else alpha = a[0]; - *d = (*d * (0xff - alpha) + *s++ * alpha + 128) >> 8; + *d = FAST_DIV255(*d * (255 - alpha) + *s * alpha); + s++; d++; a += 1 << hsub; } |