diff --git a/doc/filters.texi b/doc/filters.texi index 42f69eaacb..154508cfff 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -7351,6 +7351,38 @@ telecine NTSC input: ffmpeg -i input -vf pullup -r 24000/1001 ... @end example +@section qp + +Change video quantization parameters (QP). + +The filter accepts the following option: + +@table @option +@item qp +Set expression for quantization parameter. +@end table + +The expression is evaluated through the eval API and can contain, among others, +the following constants: + +@table @var +@item known +1 if index is not 129, 0 otherwise. + +@item qp +Sequentional index starting from -129 to 128. +@end table + +@subsection Examples + +@itemize +@item +Some equation like: +@example +qp=2+2*sin(PI*qp) +@end example +@end itemize + @section removelogo Suppress a TV station logo, using an image file to determine which diff --git a/libavfilter/Makefile b/libavfilter/Makefile index a2bac38277..37f5a65f69 100644 --- a/libavfilter/Makefile +++ b/libavfilter/Makefile @@ -167,6 +167,7 @@ OBJS-$(CONFIG_PP_FILTER) += vf_pp.o OBJS-$(CONFIG_PP7_FILTER) += vf_pp7.o OBJS-$(CONFIG_PSNR_FILTER) += vf_psnr.o dualinput.o framesync.o OBJS-$(CONFIG_PULLUP_FILTER) += vf_pullup.o +OBJS-$(CONFIG_QP_FILTER) += vf_qp.o OBJS-$(CONFIG_REMOVELOGO_FILTER) += bbox.o lswsutils.o lavfutils.o vf_removelogo.o OBJS-$(CONFIG_ROTATE_FILTER) += vf_rotate.o OBJS-$(CONFIG_SEPARATEFIELDS_FILTER) += vf_separatefields.o diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c index a330eb984f..b19da616b0 100644 --- a/libavfilter/allfilters.c +++ b/libavfilter/allfilters.c @@ -182,6 +182,7 @@ void avfilter_register_all(void) REGISTER_FILTER(PP7, pp7, vf); REGISTER_FILTER(PSNR, psnr, vf); REGISTER_FILTER(PULLUP, pullup, vf); + REGISTER_FILTER(QP, qp, vf); REGISTER_FILTER(REMOVELOGO, removelogo, vf); REGISTER_FILTER(ROTATE, rotate, vf); REGISTER_FILTER(SAB, sab, vf); diff --git a/libavfilter/vf_qp.c b/libavfilter/vf_qp.c new file mode 100644 index 0000000000..9c0679a70f --- /dev/null +++ b/libavfilter/vf_qp.c @@ -0,0 +1,152 @@ +/* + * Copyright (C) 2004 Michael Niedermayer + * + * 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 + */ + +#include +#include "libavutil/eval.h" +#include "libavutil/imgutils.h" +#include "libavutil/pixdesc.h" +#include "libavutil/opt.h" +#include "avfilter.h" +#include "formats.h" +#include "internal.h" +#include "video.h" + +typedef struct QPContext { + const AVClass *class; + char *qp_expr_str; + int8_t lut[257]; + int h, qstride; +} QPContext; + +#define OFFSET(x) offsetof(QPContext, x) +#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM + +static const AVOption qp_options[] = { + { "qp", "set qp expression", OFFSET(qp_expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS }, + { NULL } +}; + +AVFILTER_DEFINE_CLASS(qp); + +static int config_input(AVFilterLink *inlink) +{ + AVFilterContext *ctx = inlink->dst; + QPContext *s = ctx->priv; + int i; + + if (!s->qp_expr_str) + return 0; + + s->h = (inlink->h + 15) >> 4; + s->qstride = (inlink->w + 15) >> 4; + for (i = -129; i < 128; i++) { + double var_values[] = { i != -129, i, 0 }; + static const char *var_names[] = { "known", "qp", NULL }; + double temp_val; + int ret; + + ret = av_expr_parse_and_eval(&temp_val, s->qp_expr_str, + var_names, var_values, + NULL, NULL, NULL, NULL, 0, 0, ctx); + if (ret < 0) + return ret; + + s->lut[i + 129] = lrintf(temp_val); + } + + return 0; +} + +static int filter_frame(AVFilterLink *inlink, AVFrame *in) +{ + AVFilterContext *ctx = inlink->dst; + AVFilterLink *outlink = ctx->outputs[0]; + QPContext *s = ctx->priv; + AVBufferRef *out_qp_table_buf; + AVFrame *out; + const int8_t *in_qp_table; + int type, stride, ret; + + if (!s->qp_expr_str || ctx->is_disabled) + return ff_filter_frame(outlink, in); + + out_qp_table_buf = av_buffer_alloc(s->h * s->qstride); + if (!out_qp_table_buf) { + ret = AVERROR(ENOMEM); + goto fail; + } + + out = av_frame_clone(in); + if (!out) { + ret = AVERROR(ENOMEM); + goto fail; + } + + in_qp_table = av_frame_get_qp_table(in, &stride, &type); + av_frame_set_qp_table(out, out_qp_table_buf, s->qstride, type); + + if (in_qp_table) { + int y, x; + + for (y = 0; y < s->h; y++) + for (x = 0; x < s->qstride; x++) + out_qp_table_buf->data[x + s->qstride * y] = s->lut[129 + + ((int8_t)in_qp_table[x + stride * y])]; + } else { + int y, x, qp = s->lut[0]; + + for (y = 0; y < s->h; y++) + for (x = 0; x < s->qstride; x++) + out_qp_table_buf->data[x + s->qstride * y] = qp; + } + + ret = ff_filter_frame(outlink, out); +fail: + av_frame_free(&in); + return ret; +} + +static const AVFilterPad qp_inputs[] = { + { + .name = "default", + .type = AVMEDIA_TYPE_VIDEO, + .filter_frame = filter_frame, + .config_props = config_input, + }, + { NULL } +}; + +static const AVFilterPad qp_outputs[] = { + { + .name = "default", + .type = AVMEDIA_TYPE_VIDEO, + }, + { NULL } +}; + +AVFilter ff_vf_qp = { + .name = "qp", + .description = NULL_IF_CONFIG_SMALL("Change video quantization parameters."), + .priv_size = sizeof(QPContext), + .inputs = qp_inputs, + .outputs = qp_outputs, + .priv_class = &qp_class, + .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL, +};