/* * Copyright (C) 2004 Michael Niedermayer <michaelni@gmx.at> * * 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 <math.h> #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) { av_buffer_unref(&out_qp_table_buf); 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, };