[FFmpeg-devel] [PATCH v2 4/8] avfilter/overlay_subs: Add overlay_subs filter
Soft Works
softworkz at hotmail.com
Mon Aug 30 11:16:45 EEST 2021
Signed-off-by: softworkz <softworkz at hotmail.com>
---
v2 Update:
- Implemented Andreas' suggestions
- overlay_subs filter:
- removed duplicated code
- implemented direct (no pre-conversion) blending of graphical
subtitle rects
- Supported input formats:
- all packed RGB formats (with and without alpha)
- yuv420p, yuv422p, yuv444p
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/vf_overlay_subs.c | 549 ++++++++++++++++++++++++++++++++++
libavfilter/vf_overlay_subs.h | 65 ++++
4 files changed, 616 insertions(+)
create mode 100644 libavfilter/vf_overlay_subs.c
create mode 100644 libavfilter/vf_overlay_subs.h
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 82a7394adb..8130f7b46c 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -357,6 +357,7 @@ OBJS-$(CONFIG_OVERLAY_CUDA_FILTER) += vf_overlay_cuda.o framesync.o vf
OBJS-$(CONFIG_OVERLAY_OPENCL_FILTER) += vf_overlay_opencl.o opencl.o \
opencl/overlay.o framesync.o
OBJS-$(CONFIG_OVERLAY_QSV_FILTER) += vf_overlay_qsv.o framesync.o
+OBJS-$(CONFIG_OVERLAY_SUBS_FILTER) += vf_overlay_subs.o framesync.o
OBJS-$(CONFIG_OVERLAY_VULKAN_FILTER) += vf_overlay_vulkan.o vulkan.o
OBJS-$(CONFIG_OWDENOISE_FILTER) += vf_owdenoise.o
OBJS-$(CONFIG_PAD_FILTER) += vf_pad.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 73040d2824..abd0a47750 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -339,6 +339,7 @@ extern const AVFilter ff_vf_oscilloscope;
extern const AVFilter ff_vf_overlay;
extern const AVFilter ff_vf_overlay_opencl;
extern const AVFilter ff_vf_overlay_qsv;
+extern const AVFilter ff_vf_overlay_subs;
extern const AVFilter ff_vf_overlay_vulkan;
extern const AVFilter ff_vf_overlay_cuda;
extern const AVFilter ff_vf_owdenoise;
diff --git a/libavfilter/vf_overlay_subs.c b/libavfilter/vf_overlay_subs.c
new file mode 100644
index 0000000000..177f9b1cc9
--- /dev/null
+++ b/libavfilter/vf_overlay_subs.c
@@ -0,0 +1,549 @@
+/*
+ * Copyright (c) 2021 softworkz
+ *
+ * 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
+ * overlay graphical subtitles on top of a video frame
+ */
+
+#include "avfilter.h"
+#include "formats.h"
+#include "libavutil/common.h"
+#include "libavutil/eval.h"
+#include "libavutil/avstring.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/opt.h"
+#include "internal.h"
+#include "drawutils.h"
+#include "framesync.h"
+#include "vf_overlay_subs.h"
+
+#include "libavcodec/avcodec.h"
+
+static const char *const var_names[] = {
+ "main_w", "W", ///< width of the main video
+ "main_h", "H", ///< height of the main video
+ "overlay_w", "w", ///< width of the overlay video
+ "overlay_h", "h", ///< height of the overlay video
+ "hsub",
+ "vsub",
+ "x",
+ "y",
+ "n", ///< number of frame
+ "pos", ///< position in the file
+ "t", ///< timestamp expressed in seconds
+ NULL
+};
+
+#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
+
+enum EvalMode {
+ EVAL_MODE_INIT,
+ EVAL_MODE_FRAME,
+ EVAL_MODE_NB
+};
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ OverlaySubsContext *s = ctx->priv;
+
+ ff_framesync_uninit(&s->fs);
+ av_expr_free(s->x_pexpr); s->x_pexpr = NULL;
+ av_expr_free(s->y_pexpr); s->y_pexpr = NULL;
+}
+
+static inline int normalize_xy(double d, int chroma_sub)
+{
+ if (isnan(d))
+ return INT_MAX;
+ return (int)d & ~((1 << chroma_sub) - 1);
+}
+
+static void eval_expr(AVFilterContext *ctx)
+{
+ OverlaySubsContext *s = ctx->priv;
+
+ s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, NULL);
+ s->var_values[VAR_Y] = av_expr_eval(s->y_pexpr, s->var_values, NULL);
+ /* It is necessary if x is expressed from y */
+ s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, NULL);
+ s->x = normalize_xy(s->var_values[VAR_X], s->hsub);
+ s->y = normalize_xy(s->var_values[VAR_Y], s->vsub);
+}
+
+static int set_expr(AVExpr **pexpr, const char *expr, const char *option, void *log_ctx)
+{
+ int ret;
+ AVExpr *old = NULL;
+
+ if (*pexpr)
+ old = *pexpr;
+ ret = av_expr_parse(pexpr, expr, var_names,
+ NULL, NULL, NULL, NULL, 0, log_ctx);
+ if (ret < 0) {
+ av_log(log_ctx, AV_LOG_ERROR,
+ "Error when evaluating the expression '%s' for %s\n",
+ expr, option);
+ *pexpr = old;
+ return ret;
+ }
+
+ av_expr_free(old);
+ return 0;
+}
+
+static const enum AVPixelFormat alpha_pix_fmts[] = {
+ AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
+ AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA422P10,
+ AV_PIX_FMT_ARGB, AV_PIX_FMT_ABGR, AV_PIX_FMT_RGBA,
+ AV_PIX_FMT_BGRA, AV_PIX_FMT_NONE
+};
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static const enum AVPixelFormat supported_pix_fmts[] = {
+ AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P,
+ AV_PIX_FMT_ARGB, AV_PIX_FMT_RGBA,
+ AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA,
+ AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
+ AV_PIX_FMT_NONE
+ };
+
+ return ff_set_common_formats(ctx, ff_make_format_list(supported_pix_fmts));
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ OverlaySubsContext *s = ctx->priv;
+ int ret;
+
+ if ((ret = ff_framesync_init_dualinput(&s->fs, ctx)) < 0)
+ return ret;
+
+ outlink->w = ctx->inputs[MAIN]->w;
+ outlink->h = ctx->inputs[MAIN]->h;
+ outlink->time_base = ctx->inputs[MAIN]->time_base;
+
+ return ff_framesync_configure(&s->fs);
+}
+
+// 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)
+
+// calculate the non-pre-multiplied alpha, applying the general equation:
+// alpha = alpha_overlay / ( (alpha_main + alpha_overlay) - (alpha_main * alpha_overlay) )
+// (((x) << 16) - ((x) << 9) + (x)) is a faster version of: 255 * 255 * x
+// ((((x) + (y)) << 8) - ((x) + (y)) - (y) * (x)) is a faster version of: 255 * (x + y)
+#define UNPREMULTIPLY_ALPHA(x, y) ((((x) << 16) - ((x) << 9) + (x)) / ((((x) + (y)) << 8) - ((x) + (y)) - (y) * (x)))
+
+/**
+ * Blend image in src to destination buffer dst at position (x, y).
+ */
+static av_always_inline void blend_packed_rgb(const AVFilterContext *ctx,
+ const AVFrame *dst, const AVSubtitleRect *src,
+ int main_has_alpha, int x, int y,
+ int is_straight)
+{
+ OverlaySubsContext *s = ctx->priv;
+ int i, imax, j, jmax;
+ const int src_w = src->w;
+ const int src_h = src->h;
+ const int dst_w = dst->width;
+ const int dst_h = dst->height;
+ uint8_t alpha; ///< the amount of overlay to blend on to main
+ const int dr = s->main_rgba_map[R];
+ const int dg = s->main_rgba_map[G];
+ const int db = s->main_rgba_map[B];
+ const int da = s->main_rgba_map[A];
+ const int dstep = s->main_pix_step[0];
+ const int sr = s->overlay_rgba_map[R];
+ const int sg = s->overlay_rgba_map[G];
+ const int sb = s->overlay_rgba_map[B];
+ const int sa = s->overlay_rgba_map[A];
+ const int sstep = s->overlay_pix_step[0];
+ uint32_t *pal = (uint32_t *)src->data[1];
+ int slice_start, slice_end;
+ uint8_t *S, *sp, *d, *dp;
+
+ i = FFMAX(-y, 0);
+ imax = FFMIN3(-y + dst_h, FFMIN(src_h, dst_h), y + src_h);
+
+ slice_start = i;
+ slice_end = i + imax;
+
+ sp = src->data[0] + slice_start * src->linesize[0];
+ dp = dst->data[0] + (slice_start + y) * dst->linesize[0];
+
+ for (i = slice_start; i < slice_end; i++) {
+ j = FFMAX(-x, 0);
+ S = sp + (j * sstep);
+ d = dp + ((x + j) * dstep);
+
+ for (jmax = FFMIN(-x + dst_w, src_w); j < jmax; j++) {
+ uint32_t val = pal[*S];
+ const uint8_t *sval = (uint8_t *)&val;
+ alpha = sval[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) {
+ const uint8_t alpha_d = d[da];
+ alpha = UNPREMULTIPLY_ALPHA(alpha, alpha_d);
+ }
+
+ switch (alpha) {
+ case 0:
+ break;
+ case 255:
+ d[dr] = sval[sr];
+ d[dg] = sval[sg];
+ d[db] = sval[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] = is_straight ? FAST_DIV255(d[dr] * (255 - alpha) + sval[sr] * alpha) :
+ FFMIN(FAST_DIV255(d[dr] * (255 - alpha)) + sval[sr], 255);
+ d[dg] = is_straight ? FAST_DIV255(d[dg] * (255 - alpha) + sval[sg] * alpha) :
+ FFMIN(FAST_DIV255(d[dg] * (255 - alpha)) + sval[sg], 255);
+ d[db] = is_straight ? FAST_DIV255(d[db] * (255 - alpha) + sval[sb] * alpha) :
+ FFMIN(FAST_DIV255(d[db] * (255 - alpha)) + sval[sb], 255);
+ }
+
+ if (main_has_alpha) {
+ switch (alpha) {
+ case 0:
+ break;
+ case 255:
+ d[da] = sval[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];
+ }
+}
+
+static av_always_inline void blend_plane_8_8bits(const AVFilterContext *ctx, const AVFrame *dst, const AVSubtitleRect *src,
+ const uint32_t *yuv_pal, int src_w, int src_h, int dst_w, int dst_h, int plane, int hsub, int vsub,
+ int x, int y, int dst_plane, int dst_offset, int dst_step)
+{
+ OverlaySubsContext *octx = ctx->priv;
+ int src_wp = AV_CEIL_RSHIFT(src_w, hsub);
+ int src_hp = AV_CEIL_RSHIFT(src_h, vsub);
+ int dst_wp = AV_CEIL_RSHIFT(dst_w, hsub);
+ int dst_hp = AV_CEIL_RSHIFT(dst_h, vsub);
+ int yp = y >> vsub;
+ int xp = x >> hsub;
+ uint8_t *s, *sp, *d, *dp, *dap;
+ int imax, i, j, jmax;
+ const int sstep = octx->overlay_pix_step[0];
+ int slice_start, slice_end;
+
+ i = FFMAX(-yp, 0); \
+ imax = FFMIN3(-yp + dst_hp, FFMIN(src_hp, dst_hp), yp + src_hp); \
+
+ slice_start = i;
+ slice_end = i + imax;
+
+ sp = src->data[0] + slice_start * src->linesize[0];
+ dp = dst->data[dst_plane] + (yp + slice_start) * dst->linesize[dst_plane] + dst_offset;
+
+ dap = dst->data[3] + ((yp + slice_start) << vsub) * dst->linesize[3];
+
+ for (i = slice_start; i < slice_end; i++) {
+ j = FFMAX(-xp, 0);
+ d = dp + (xp + j) * dst_step;
+ s = sp + j * sstep;
+ jmax = FFMIN(-xp + dst_wp, src_wp);
+
+ for (; j < jmax; j++) {
+ uint32_t val = yuv_pal[*s];
+ const uint8_t *sval = (uint8_t *)&val;
+ const int alpha = sval[3];
+
+ *d = (*d * (255 - alpha) + sval[plane] * alpha + 128) * 257 >> 16;
+ d += dst_step;
+ s += (1 << hsub);
+ }
+ dp += dst->linesize[dst_plane];
+ sp += src->linesize[plane];
+ dap += (1 << vsub) * dst->linesize[3];
+ }
+}
+
+#define RGB2Y(r, g, b) (uint8_t)(((66 * (r) + 129 * (g) + 25 * (b) + 128) >> 8) + 16)
+#define RGB2U(r, g, b) (uint8_t)(((-38 * (r) - 74 * (g) + 112 * (b) + 128) >> 8) + 128)
+#define RGB2V(r, g, b) (uint8_t)(((112 * (r) - 94 * (g) - 18 * (b) + 128) >> 8) + 128)
+/* Converts R8 G8 B8 color to YUV. */
+static av_always_inline void rgb_2_yuv(uint8_t r, uint8_t g, uint8_t b, uint8_t* y, uint8_t* u, uint8_t* v)
+{
+ *y = RGB2Y((int)r, (int)g, (int)b);
+ *u = RGB2U((int)r, (int)g, (int)b);
+ *v = RGB2V((int)r, (int)g, (int)b);
+}
+
+static av_always_inline void blend_yuv_8_8bits(AVFilterContext *ctx, AVFrame *dst, const AVSubtitleRect *src, int hsub, int vsub, int x, int y)
+{
+ OverlaySubsContext *s = ctx->priv;
+ const int src_w = src->w;
+ const int src_h = src->h;
+ const int dst_w = dst->width;
+ const int dst_h = dst->height;
+ const int sr = s->overlay_rgba_map[R];
+ const int sg = s->overlay_rgba_map[G];
+ const int sb = s->overlay_rgba_map[B];
+ const int sa = s->overlay_rgba_map[A];
+ uint32_t *pal = (uint32_t *)src->data[1];
+ uint32_t yuvpal[256];
+
+ for (int i = 0; i < 256; ++i) {
+ const uint8_t *rgba = (uint8_t *)&pal[i];
+ uint8_t *yuva = (uint8_t *)&yuvpal[i];
+ rgb_2_yuv(rgba[sr], rgba[sg], rgba[sb], &yuva[Y], &yuva[U], &yuva[V]);
+ yuva[3] = rgba[sa];
+ }
+
+ blend_plane_8_8bits(ctx, dst, src, yuvpal, src_w, src_h, dst_w, dst_h, Y, 0, 0, x, y, s->main_desc->comp[Y].plane, s->main_desc->comp[Y].offset, s->main_desc->comp[Y].step);
+ blend_plane_8_8bits(ctx, dst, src, yuvpal, src_w, src_h, dst_w, dst_h, U, hsub, vsub, x, y, s->main_desc->comp[U].plane, s->main_desc->comp[U].offset, s->main_desc->comp[U].step);
+ blend_plane_8_8bits(ctx, dst, src, yuvpal, src_w, src_h, dst_w, dst_h, V, hsub, vsub, x, y, s->main_desc->comp[V].plane, s->main_desc->comp[V].offset, s->main_desc->comp[V].step);
+}
+
+static int config_input_main(AVFilterLink *inlink)
+{
+ int ret;
+ AVFilterContext *ctx = inlink->dst;
+ OverlaySubsContext *s = inlink->dst->priv;
+ const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
+ const AVPixFmtDescriptor *pix_desc_overlay = av_pix_fmt_desc_get(AV_PIX_FMT_PAL8);
+
+ av_image_fill_max_pixsteps(s->main_pix_step, NULL, pix_desc);
+ av_image_fill_max_pixsteps(s->overlay_pix_step, NULL, pix_desc_overlay);
+ ff_fill_rgba_map(s->overlay_rgba_map, AV_PIX_FMT_RGB32);
+
+ s->hsub = pix_desc->log2_chroma_w;
+ s->vsub = pix_desc->log2_chroma_h;
+
+ s->main_desc = pix_desc;
+
+ s->main_is_packed_rgb = ff_fill_rgba_map(s->main_rgba_map, inlink->format) >= 0;
+ s->main_has_alpha = ff_fmt_is_in(inlink->format, alpha_pix_fmts);
+
+ /* Finish the configuration by evaluating the expressions
+ now when both inputs are configured. */
+ s->var_values[VAR_MAIN_W ] = s->var_values[VAR_MW] = ctx->inputs[MAIN ]->w;
+ s->var_values[VAR_MAIN_H ] = s->var_values[VAR_MH] = ctx->inputs[MAIN ]->h;
+ s->var_values[VAR_OVERLAY_W] = s->var_values[VAR_OW] = ctx->inputs[OVERLAY]->w;
+ s->var_values[VAR_OVERLAY_H] = s->var_values[VAR_OH] = ctx->inputs[OVERLAY]->h;
+ s->var_values[VAR_HSUB] = 1<<pix_desc->log2_chroma_w;
+ s->var_values[VAR_VSUB] = 1<<pix_desc->log2_chroma_h;
+ s->var_values[VAR_X] = NAN;
+ s->var_values[VAR_Y] = NAN;
+ s->var_values[VAR_N] = 0;
+ s->var_values[VAR_T] = NAN;
+ s->var_values[VAR_POS] = NAN;
+
+ if ((ret = set_expr(&s->x_pexpr, s->x_expr, "x", ctx)) < 0 ||
+ (ret = set_expr(&s->y_pexpr, s->y_expr, "y", ctx)) < 0)
+ return ret;
+
+ if (s->eval_mode == EVAL_MODE_INIT) {
+ eval_expr(ctx);
+ av_log(ctx, AV_LOG_VERBOSE, "x:%f xi:%d y:%f yi:%d\n",
+ s->var_values[VAR_X], s->x,
+ s->var_values[VAR_Y], s->y);
+ }
+
+ av_log(ctx, AV_LOG_VERBOSE,
+ "main w:%d h:%d fmt:%s overlay w:%d h:%d fmt:%s\n",
+ ctx->inputs[MAIN]->w, ctx->inputs[MAIN]->h,
+ av_get_pix_fmt_name(ctx->inputs[MAIN]->format),
+ ctx->inputs[OVERLAY]->w, ctx->inputs[OVERLAY]->h,
+ av_get_pix_fmt_name(ctx->inputs[OVERLAY]->format));
+ return 0;
+}
+
+static int do_blend(FFFrameSync *fs)
+{
+ AVFilterContext *ctx = fs->parent;
+ AVFrame *mainpic, *second;
+ OverlaySubsContext *s = ctx->priv;
+ AVFilterLink *inlink = ctx->inputs[0];
+ int ret;
+
+ ret = ff_framesync_dualinput_get_writable(fs, &mainpic, &second);
+ if (ret < 0)
+ return ret;
+ if (!second)
+ return ff_filter_frame(ctx->outputs[0], mainpic);
+
+ if (s->eval_mode == EVAL_MODE_FRAME) {
+ int64_t pos = mainpic->pkt_pos;
+
+ s->var_values[VAR_N] = inlink->frame_count_out;
+ s->var_values[VAR_T] = mainpic->pts == AV_NOPTS_VALUE ?
+ NAN : mainpic->pts * av_q2d(inlink->time_base);
+ s->var_values[VAR_POS] = pos == -1 ? NAN : pos;
+
+ s->var_values[VAR_OVERLAY_W] = s->var_values[VAR_OW] = second->width;
+ s->var_values[VAR_OVERLAY_H] = s->var_values[VAR_OH] = second->height;
+ s->var_values[VAR_MAIN_W ] = s->var_values[VAR_MW] = mainpic->width;
+ s->var_values[VAR_MAIN_H ] = s->var_values[VAR_MH] = mainpic->height;
+
+ eval_expr(ctx);
+ av_log(ctx, AV_LOG_DEBUG, "n:%f t:%f pos:%f x:%f xi:%d y:%f yi:%d\n",
+ s->var_values[VAR_N], s->var_values[VAR_T], s->var_values[VAR_POS],
+ s->var_values[VAR_X], s->x,
+ s->var_values[VAR_Y], s->y);
+ }
+
+ if (second->buf[0] && second->buf[0]->data) {
+ const AVSubtitle *sub = (AVSubtitle *)second->buf[0]->data;
+ unsigned num_rects, i;
+
+ num_rects = sub->num_rects;
+
+ for (i = 0; i < num_rects; i++) {
+ const AVSubtitleRect *sub_rect = sub->rects[i];
+
+ if (sub_rect->type != SUBTITLE_BITMAP) {
+ av_log(NULL, AV_LOG_WARNING, "sub2video: non-bitmap subtitle\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ switch (inlink->format) {
+ case AV_PIX_FMT_YUV420P:
+ blend_yuv_8_8bits(ctx, mainpic, sub_rect, 1, 1, sub_rect->x + s->x, sub_rect->y + s->y);
+ break;
+ case AV_PIX_FMT_YUV422P:
+ blend_yuv_8_8bits(ctx, mainpic, sub_rect, 1, 0, sub_rect->x + s->x, sub_rect->y + s->y);
+ break;
+ case AV_PIX_FMT_YUV444P:
+ blend_yuv_8_8bits(ctx, mainpic, sub_rect, 0, 0, sub_rect->x + s->x, sub_rect->y + s->y);
+ break;
+ case AV_PIX_FMT_RGB24:
+ case AV_PIX_FMT_BGR24:
+ case AV_PIX_FMT_ARGB:
+ case AV_PIX_FMT_RGBA:
+ case AV_PIX_FMT_BGRA:
+ case AV_PIX_FMT_ABGR:
+ blend_packed_rgb(ctx, mainpic, sub_rect, s->main_has_alpha, sub_rect->x + s->x, sub_rect->y + s->y, 1);
+ break;
+ default:
+ av_assert0(0);
+ break;
+ }
+ }
+ }
+
+ return ff_filter_frame(ctx->outputs[0], mainpic);
+}
+
+static av_cold int init(AVFilterContext *ctx)
+{
+ OverlaySubsContext *s = ctx->priv;
+
+ s->fs.on_event = do_blend;
+ return 0;
+}
+
+static int activate(AVFilterContext *ctx)
+{
+ OverlaySubsContext *s = ctx->priv;
+ return ff_framesync_activate(&s->fs);
+}
+
+#define OFFSET(x) offsetof(OverlaySubsContext, x)
+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption overlay_subs_options[] = {
+ { "x", "set the x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "0"}, 0, 0, FLAGS },
+ { "y", "set the y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "0"}, 0, 0, FLAGS },
+ { "eof_action", "Action to take when encountering EOF from secondary input ",
+ OFFSET(fs.opt_eof_action), AV_OPT_TYPE_INT, { .i64 = EOF_ACTION_REPEAT },
+ EOF_ACTION_REPEAT, EOF_ACTION_PASS, .flags = FLAGS, "eof_action" },
+ { "repeat", "Repeat the previous frame.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_REPEAT }, .flags = FLAGS, "eof_action" },
+ { "endall", "End both streams.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_ENDALL }, .flags = FLAGS, "eof_action" },
+ { "pass", "Pass through the main input.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_PASS }, .flags = FLAGS, "eof_action" },
+ { "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_FRAME}, 0, EVAL_MODE_NB-1, FLAGS, "eval" },
+ { "init", "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
+ { "frame", "eval expressions per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
+ { "shortest", "force termination when the shortest input terminates", OFFSET(fs.opt_shortest), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
+ { "repeatlast", "repeat overlay of the last overlay frame", OFFSET(fs.opt_repeatlast), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
+ { NULL }
+};
+
+FRAMESYNC_DEFINE_CLASS(overlay_subs, OverlaySubsContext, fs);
+
+static const AVFilterPad overlay_subs_inputs[] = {
+ {
+ .name = "main",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_input_main,
+ .flags = AVFILTERPAD_FLAG_NEEDS_WRITABLE,
+ },
+ {
+ .name = "overlay",
+ .type = AVMEDIA_TYPE_SUBTITLE,
+ },
+ { NULL }
+};
+
+static const AVFilterPad overlay_subs_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_output,
+ },
+ { NULL }
+};
+
+const AVFilter ff_vf_overlay_subs = {
+ .name = "overlay_subs",
+ .description = NULL_IF_CONFIG_SMALL("Overlay graphical subtitles on top of the input."),
+ .preinit = overlay_subs_framesync_preinit,
+ .init = init,
+ .uninit = uninit,
+ .priv_size = sizeof(OverlaySubsContext),
+ .priv_class = &overlay_subs_class,
+ .query_formats = query_formats,
+ .activate = activate,
+ .inputs = overlay_subs_inputs,
+ .outputs = overlay_subs_outputs,
+};
diff --git a/libavfilter/vf_overlay_subs.h b/libavfilter/vf_overlay_subs.h
new file mode 100644
index 0000000000..08e8637bff
--- /dev/null
+++ b/libavfilter/vf_overlay_subs.h
@@ -0,0 +1,65 @@
+/*
+ * 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
+ */
+
+#ifndef AVFILTER_OVERLAY_SUBS_H
+#define AVFILTER_OVERLAY_SUBS_H
+
+#include "libavutil/eval.h"
+#include "libavutil/pixdesc.h"
+#include "framesync.h"
+#include "avfilter.h"
+
+enum var_name {
+ VAR_MAIN_W, VAR_MW,
+ VAR_MAIN_H, VAR_MH,
+ VAR_OVERLAY_W, VAR_OW,
+ VAR_OVERLAY_H, VAR_OH,
+ VAR_HSUB,
+ VAR_VSUB,
+ VAR_X,
+ VAR_Y,
+ VAR_N,
+ VAR_POS,
+ VAR_T,
+ VAR_VARS_NB
+};
+
+typedef struct OverlaySubsContext {
+ const AVClass *class;
+ int x, y; ///< position of overlaid picture
+
+ uint8_t main_is_packed_rgb;
+ uint8_t main_rgba_map[4];
+ uint8_t main_has_alpha;
+ uint8_t overlay_rgba_map[4];
+ int eval_mode; ///< EvalMode
+
+ FFFrameSync fs;
+
+ 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
+ const AVPixFmtDescriptor *main_desc; ///< format descriptor for main input
+
+ double var_values[VAR_VARS_NB];
+ char *x_expr, *y_expr;
+
+ AVExpr *x_pexpr, *y_pexpr;
+} OverlaySubsContext;
+
+#endif /* AVFILTER_OVERLAY_SUBS_H */
--
2.30.2.windows.1
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