FFmpeg
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fast deshake / depan video filter More...
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
#include "libavutil/common.h"
#include "libavutil/mem.h"
#include "libavutil/pixdesc.h"
#include "libavcodec/dsputil.h"
#include "transform.h"
Go to the source code of this file.
Data Structures | |
struct | IntMotionVector |
struct | MotionVector |
struct | Transform |
struct | DeshakeContext |
Macros | |
#define | CHROMA_WIDTH(link) -((-link->w) >> av_pix_fmt_desc_get(link->format)->log2_chroma_w) |
#define | CHROMA_HEIGHT(link) -((-link->h) >> av_pix_fmt_desc_get(link->format)->log2_chroma_h) |
#define | CMP(i, j) |
Enumerations | |
enum | SearchMethod { EXHAUSTIVE, SMART_EXHAUSTIVE, SEARCH_COUNT } |
Functions | |
static int | cmp (const double *a, const double *b) |
static double | clean_mean (double *values, int count) |
Cleaned mean (cuts off 20% of values to remove outliers and then averages) | |
static void | find_block_motion (DeshakeContext *deshake, uint8_t *src1, uint8_t *src2, int cx, int cy, int stride, IntMotionVector *mv) |
Find the most likely shift in motion between two frames for a given macroblock. | |
static int | block_contrast (uint8_t *src, int x, int y, int stride, int blocksize) |
Find the contrast of a given block. | |
static double | block_angle (int x, int y, int cx, int cy, IntMotionVector *shift) |
Find the rotation for a given block. | |
static void | find_motion (DeshakeContext *deshake, uint8_t *src1, uint8_t *src2, int width, int height, int stride, Transform *t) |
Find the estimated global motion for a scene given the most likely shift for each block in the frame. | |
static av_cold int | init (AVFilterContext *ctx, const char *args) |
static int | query_formats (AVFilterContext *ctx) |
static int | config_props (AVFilterLink *link) |
static av_cold void | uninit (AVFilterContext *ctx) |
static int | filter_frame (AVFilterLink *link, AVFilterBufferRef *in) |
Variables | |
static const AVFilterPad | deshake_inputs [] |
static const AVFilterPad | deshake_outputs [] |
AVFilter | avfilter_vf_deshake |
fast deshake / depan video filter
SAD block-matching motion compensation to fix small changes in horizontal and/or vertical shift. This filter helps remove camera shake from hand-holding a camera, bumping a tripod, moving on a vehicle, etc.
Algorithm:
TODO:
Dark Shikari links to http://wiki.videolan.org/SoC_x264_2010#GPU_Motion_Estimation_2 for an algorithm similar to what could be used here to get the gmv It requires only a couple diamond searches + fast downscaling
Special thanks to Jason Kotenko for his help with the algorithm and my inability to see simple errors in C code.
Definition in file vf_deshake.c.
#define CHROMA_WIDTH | ( | link | ) | -((-link->w) >> av_pix_fmt_desc_get(link->format)->log2_chroma_w) |
Definition at line 63 of file vf_deshake.c.
Referenced by filter_frame().
#define CHROMA_HEIGHT | ( | link | ) | -((-link->h) >> av_pix_fmt_desc_get(link->format)->log2_chroma_h) |
Definition at line 64 of file vf_deshake.c.
Referenced by filter_frame().
#define CMP | ( | i, | |
j | |||
) |
Referenced by find_block_motion().
enum SearchMethod |
EXHAUSTIVE |
Search all possible positions. |
SMART_EXHAUSTIVE |
Search most possible positions (faster) |
SEARCH_COUNT |
Definition at line 66 of file vf_deshake.c.
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Definition at line 109 of file vf_deshake.c.
Referenced by clean_mean().
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Cleaned mean (cuts off 20% of values to remove outliers and then averages)
Definition at line 117 of file vf_deshake.c.
Referenced by find_motion().
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Find the most likely shift in motion between two frames for a given macroblock.
Test each block against several shifts given by the rx and ry attributes. Searches using a simple matrix of those shifts and chooses the most likely shift by the smallest difference in blocks.
Definition at line 138 of file vf_deshake.c.
Referenced by find_motion().
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Find the contrast of a given block.
When searching for global motion we really only care about the high contrast blocks, so using this method we can actually skip blocks we don't care much about.
Definition at line 209 of file vf_deshake.c.
Referenced by find_motion().
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Find the rotation for a given block.
Definition at line 233 of file vf_deshake.c.
Referenced by find_motion().
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Find the estimated global motion for a scene given the most likely shift for each block in the frame.
The global motion is estimated to be the same as the motion from most blocks in the frame, so if most blocks move one pixel to the right and two pixels down, this would yield a motion vector (1, -2).
Definition at line 254 of file vf_deshake.c.
Referenced by filter_frame().
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Definition at line 335 of file vf_deshake.c.
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Definition at line 388 of file vf_deshake.c.
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Definition at line 401 of file vf_deshake.c.
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Definition at line 417 of file vf_deshake.c.
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Definition at line 429 of file vf_deshake.c.
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Definition at line 540 of file vf_deshake.c.
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Definition at line 551 of file vf_deshake.c.
AVFilter avfilter_vf_deshake |
Definition at line 559 of file vf_deshake.c.