/*
* Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* FFmpeg is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU 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
* Motion Compensation Deinterlacer
* Ported from MPlayer libmpcodecs/vf_mcdeint.c.
*
* Known Issues:
*
* The motion estimation is somewhat at the mercy of the input, if the
* input frames are created purely based on spatial interpolation then
* for example a thin black line or another random and not
* interpolateable pattern will cause problems.
* Note: completely ignoring the "unavailable" lines during motion
* estimation did not look any better, so the most obvious solution
* would be to improve tfields or penalize problematic motion vectors.
*
* If non iterative ME is used then snow currently ignores the OBMC
* window and as a result sometimes creates artifacts.
*
* Only past frames are used, we should ideally use future frames too,
* something like filtering the whole movie in forward and then
* backward direction seems like a interesting idea but the current
* filter framework is FAR from supporting such things.
*
* Combining the motion compensated image with the input image also is
* not as trivial as it seems, simple blindly taking even lines from
* one and odd ones from the other does not work at all as ME/MC
* sometimes has nothing in the previous frames which matches the
* current. The current algorithm has been found by trial and error
* and almost certainly can be improved...
*/
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "libavcodec/avcodec.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
enum MCDeintMode {
MODE_FAST = 0,
MODE_MEDIUM,
MODE_SLOW,
MODE_EXTRA_SLOW,
MODE_NB,
};
enum MCDeintParity {
PARITY_TFF = 0, ///< top field first
PARITY_BFF = 1, ///< bottom field first
};
typedef struct {
const AVClass *class;
enum MCDeintMode mode;
enum MCDeintParity parity;
int qp;
AVCodecContext *enc_ctx;
} MCDeintContext;
#define OFFSET(x) offsetof(MCDeintContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
#define CONST(name, help, val, unit) { name, help, 0, AV_OPT_TYPE_CONST, {.i64=val}, INT_MIN, INT_MAX, FLAGS, unit }
static const AVOption mcdeint_options[] = {
{ "mode", "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_FAST}, 0, MODE_NB-1, FLAGS, .unit="mode" },
CONST("fast", NULL, MODE_FAST, "mode"),
CONST("medium", NULL, MODE_MEDIUM, "mode"),
CONST("slow", NULL, MODE_SLOW, "mode"),
CONST("extra_slow", NULL, MODE_EXTRA_SLOW, "mode"),
{ "parity", "set the assumed picture field parity", OFFSET(parity), AV_OPT_TYPE_INT, {.i64=PARITY_BFF}, -1, 1, FLAGS, "parity" },
CONST("tff", "assume top field first", PARITY_TFF, "parity"),
CONST("bff", "assume bottom field first", PARITY_BFF, "parity"),
{ "qp", "set qp", OFFSET(qp), AV_OPT_TYPE_INT, {.i64=1}, INT_MIN, INT_MAX, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(mcdeint);
static int config_props(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
MCDeintContext *mcdeint = ctx->priv;
AVCodec *enc;
AVCodecContext *enc_ctx;
AVDictionary *opts = NULL;
int ret;
if (!(enc = avcodec_find_encoder(AV_CODEC_ID_SNOW))) {
av_log(ctx, AV_LOG_ERROR, "Snow encoder is not enabled in libavcodec\n");
return AVERROR(EINVAL);
}
mcdeint->enc_ctx = avcodec_alloc_context3(enc);
if (!mcdeint->enc_ctx)
return AVERROR(ENOMEM);
enc_ctx = mcdeint->enc_ctx;
enc_ctx->width = inlink->w;
enc_ctx->height = inlink->h;
enc_ctx->time_base = (AVRational){1,25}; // meaningless
enc_ctx->gop_size = 300;
enc_ctx->max_b_frames = 0;
enc_ctx->pix_fmt = AV_PIX_FMT_YUV420P;
enc_ctx->flags = CODEC_FLAG_QSCALE | CODEC_FLAG_LOW_DELAY;
enc_ctx->strict_std_compliance = FF_COMPLIANCE_EXPERIMENTAL;
enc_ctx->global_quality = 1;
enc_ctx->me_cmp = enc_ctx->me_sub_cmp = FF_CMP_SAD;
enc_ctx->mb_cmp = FF_CMP_SSE;
av_dict_set(&opts, "memc_only", "1", 0);
switch (mcdeint->mode) {
case MODE_EXTRA_SLOW:
enc_ctx->refs = 3;
case MODE_SLOW:
enc_ctx->me_method = ME_ITER;
case MODE_MEDIUM:
enc_ctx->flags |= CODEC_FLAG_4MV;
enc_ctx->dia_size = 2;
case MODE_FAST:
enc_ctx->flags |= CODEC_FLAG_QPEL;
}
ret = avcodec_open2(enc_ctx, enc, &opts);
av_dict_free(&opts);
if (ret < 0)
return ret;
return 0;
}
static av_cold void uninit(AVFilterContext *ctx)
{
MCDeintContext *mcdeint = ctx->priv;
if (mcdeint->enc_ctx) {
avcodec_close(mcdeint->enc_ctx);
av_freep(&mcdeint->enc_ctx);
}
}
static int query_formats(AVFilterContext *ctx)
{
static const enum PixelFormat pix_fmts[] = {
AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE
};
ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *inpic)
{
MCDeintContext *mcdeint = inlink->dst->priv;
AVFilterLink *outlink = inlink->dst->outputs[0];
AVFrame *outpic, *frame_dec;
AVPacket pkt;
int x, y, i, ret, got_frame = 0;
outpic = ff_get_video_buffer(outlink, outlink->w, outlink->h);
if (!outpic) {
av_frame_free(&inpic);
return AVERROR(ENOMEM);
}
av_frame_copy_props(outpic, inpic);
inpic->quality = mcdeint->qp * FF_QP2LAMBDA;
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
ret = avcodec_encode_video2(mcdeint->enc_ctx, &pkt, inpic, &got_frame);
if (ret < 0)
goto end;
frame_dec = mcdeint->enc_ctx->coded_frame;
for (i = 0; i < 3; i++) {
int is_chroma = !!i;
int w = FF_CEIL_RSHIFT(inlink->w, is_chroma);
int h = FF_CEIL_RSHIFT(inlink->h, is_chroma);
int fils = frame_dec->linesize[i];
int srcs = inpic ->linesize[i];
int dsts = outpic ->linesize[i];
for (y = 0; y < h; y++) {
if ((y ^ mcdeint->parity) & 1) {
for (x = 0; x < w; x++) {
uint8_t *filp = &frame_dec->data[i][x + y*fils];
uint8_t *srcp = &inpic ->data[i][x + y*srcs];
uint8_t *dstp = &outpic ->data[i][x + y*dsts];
if (y > 0 && y < h-1){
int is_edge = x < 3 || x > w-4;
int diff0 = filp[-fils] - srcp[-srcs];
int diff1 = filp[+fils] - srcp[+srcs];
int temp = filp[0];
#define DELTA(j) av_clip(j, -x, w-1-x)
#define GET_SCORE_EDGE(j)\
FFABS(srcp[-srcs+DELTA(-1+(j))] - srcp[+srcs+DELTA(-1-(j))])+\
FFABS(srcp[-srcs+DELTA(j) ] - srcp[+srcs+DELTA( -(j))])+\
FFABS(srcp[-srcs+DELTA(1+(j)) ] - srcp[+srcs+DELTA( 1-(j))])
#define GET_SCORE(j)\
FFABS(srcp[-srcs-1+(j)] - srcp[+srcs-1-(j)])+\
FFABS(srcp[-srcs +(j)] - srcp[+srcs -(j)])+\
FFABS(srcp[-srcs+1+(j)] - srcp[+srcs+1-(j)])
#define CHECK_EDGE(j)\
{ int score = GET_SCORE_EDGE(j);\
if (score < spatial_score){\
spatial_score = score;\
diff0 = filp[-fils+DELTA(j)] - srcp[-srcs+DELTA(j)];\
diff1 = filp[+fils+DELTA(-(j))] - srcp[+srcs+DELTA(-(j))];\
#define CHECK(j)\
{ int score = GET_SCORE(j);\
if (score < spatial_score){\
spatial_score= score;\
diff0 = filp[-fils+(j)] - srcp[-srcs+(j)];\
diff1 = filp[+fils-(j)] - srcp[+srcs-(j)];\
if (is_edge) {
int spatial_score = GET_SCORE_EDGE(0) - 1;
CHECK_EDGE(-1) CHECK_EDGE(-2) }} }}
CHECK_EDGE( 1) CHECK_EDGE( 2) }} }}
} else {
int spatial_score = GET_SCORE(0) - 1;
CHECK(-1) CHECK(-2) }} }}
CHECK( 1) CHECK( 2) }} }}
}
if (diff0 + diff1 > 0)
temp -= (diff0 + diff1 - FFABS(FFABS(diff0) - FFABS(diff1)) / 2) / 2;
else
temp -= (diff0 + diff1 + FFABS(FFABS(diff0) - FFABS(diff1)) / 2) / 2;
*filp = *dstp = temp > 255U ? ~(temp>>31) : temp;
} else {
*dstp = *filp;
}
}
}
}
for (y = 0; y < h; y++) {
if (!((y ^ mcdeint->parity) & 1)) {
for (x = 0; x < w; x++) {
frame_dec->data[i][x + y*fils] =
outpic ->data[i][x + y*dsts] = inpic->data[i][x + y*srcs];
}
}
}
}
mcdeint->parity ^= 1;
end:
av_free_packet(&pkt);
av_frame_free(&inpic);
if (ret < 0) {
av_frame_free(&outpic);
return ret;
}
return ff_filter_frame(outlink, outpic);
}
static const AVFilterPad mcdeint_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
.config_props = config_props,
},
{ NULL }
};
static const AVFilterPad mcdeint_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter avfilter_vf_mcdeint = {
.name = "mcdeint",
.description = NULL_IF_CONFIG_SMALL("Apply motion compensating deinterlacing."),
.priv_size = sizeof(MCDeintContext),
.uninit = uninit,
.query_formats = query_formats,
.inputs = mcdeint_inputs,
.outputs = mcdeint_outputs,
.priv_class = &mcdeint_class,
};