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Diffstat (limited to 'libavfilter/vf_deshake.c')
| -rw-r--r-- | libavfilter/vf_deshake.c | 556 |
1 files changed, 556 insertions, 0 deletions
diff --git a/libavfilter/vf_deshake.c b/libavfilter/vf_deshake.c new file mode 100644 index 0000000..bb20551 --- /dev/null +++ b/libavfilter/vf_deshake.c @@ -0,0 +1,556 @@ +/* + * Copyright (C) 2010 Georg Martius <georg.martius@web.de> + * Copyright (C) 2010 Daniel G. Taylor <dan@programmer-art.org> + * + * 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 + * 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: + * - For each frame with one previous reference frame + * - For each block in the frame + * - If contrast > threshold then find likely motion vector + * - For all found motion vectors + * - Find most common, store as global motion vector + * - Find most likely rotation angle + * - Transform image along global motion + * + * TODO: + * - Fill frame edges based on previous/next reference frames + * - Fill frame edges by stretching image near the edges? + * - Can this be done quickly and look decent? + * + * 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. + */ + +#include "avfilter.h" +#include "libavutil/common.h" +#include "libavutil/mem.h" +#include "libavutil/pixdesc.h" +#include "libavcodec/dsputil.h" + +#include "transform.h" + +#define CHROMA_WIDTH(link) -((-link->w) >> av_pix_fmt_descriptors[link->format].log2_chroma_w) +#define CHROMA_HEIGHT(link) -((-link->h) >> av_pix_fmt_descriptors[link->format].log2_chroma_h) + +enum SearchMethod { + EXHAUSTIVE, ///< Search all possible positions + SMART_EXHAUSTIVE, ///< Search most possible positions (faster) + SEARCH_COUNT +}; + +typedef struct { + int x; ///< Horizontal shift + int y; ///< Vertical shift +} IntMotionVector; + +typedef struct { + double x; ///< Horizontal shift + double y; ///< Vertical shift +} MotionVector; + +typedef struct { + MotionVector vector; ///< Motion vector + double angle; ///< Angle of rotation + double zoom; ///< Zoom percentage +} Transform; + +typedef struct { + AVClass av_class; + AVFilterBufferRef *ref; ///< Previous frame + int rx; ///< Maximum horizontal shift + int ry; ///< Maximum vertical shift + enum FillMethod edge; ///< Edge fill method + int blocksize; ///< Size of blocks to compare + int contrast; ///< Contrast threshold + enum SearchMethod search; ///< Motion search method + AVCodecContext *avctx; + DSPContext c; ///< Context providing optimized SAD methods + Transform last; ///< Transform from last frame + int refcount; ///< Number of reference frames (defines averaging window) + FILE *fp; + Transform avg; + int cw; ///< Crop motion search to this box + int ch; + int cx; + int cy; +} DeshakeContext; + +static int cmp(const double *a, const double *b) +{ + return *a < *b ? -1 : ( *a > *b ? 1 : 0 ); +} + +/** + * Cleaned mean (cuts off 20% of values to remove outliers and then averages) + */ +static double clean_mean(double *values, int count) +{ + double mean = 0; + int cut = count / 5; + int x; + + qsort(values, count, sizeof(double), (void*)cmp); + + for (x = cut; x < count - cut; x++) { + mean += values[x]; + } + + return mean / (count - cut * 2); +} + +/** + * 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. + */ +static void find_block_motion(DeshakeContext *deshake, uint8_t *src1, + uint8_t *src2, int cx, int cy, int stride, + IntMotionVector *mv) +{ + int x, y; + int diff; + int smallest = INT_MAX; + int tmp, tmp2; + + #define CMP(i, j) deshake->c.sad[0](deshake, src1 + cy * stride + cx, \ + src2 + (j) * stride + (i), stride, \ + deshake->blocksize) + + if (deshake->search == EXHAUSTIVE) { + // Compare every possible position - this is sloooow! + for (y = -deshake->ry; y <= deshake->ry; y++) { + for (x = -deshake->rx; x <= deshake->rx; x++) { + diff = CMP(cx - x, cy - y); + if (diff < smallest) { + smallest = diff; + mv->x = x; + mv->y = y; + } + } + } + } else if (deshake->search == SMART_EXHAUSTIVE) { + // Compare every other possible position and find the best match + for (y = -deshake->ry + 1; y < deshake->ry - 2; y += 2) { + for (x = -deshake->rx + 1; x < deshake->rx - 2; x += 2) { + diff = CMP(cx - x, cy - y); + if (diff < smallest) { + smallest = diff; + mv->x = x; + mv->y = y; + } + } + } + + // Hone in on the specific best match around the match we found above + tmp = mv->x; + tmp2 = mv->y; + + for (y = tmp2 - 1; y <= tmp2 + 1; y++) { + for (x = tmp - 1; x <= tmp + 1; x++) { + if (x == tmp && y == tmp2) + continue; + + diff = CMP(cx - x, cy - y); + if (diff < smallest) { + smallest = diff; + mv->x = x; + mv->y = y; + } + } + } + } + + if (smallest > 512) { + mv->x = -1; + mv->y = -1; + } + emms_c(); + //av_log(NULL, AV_LOG_ERROR, "%d\n", smallest); + //av_log(NULL, AV_LOG_ERROR, "Final: (%d, %d) = %d x %d\n", cx, cy, mv->x, mv->y); +} + +/** + * 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. + */ +static int block_contrast(uint8_t *src, int x, int y, int stride, int blocksize) +{ + int highest = 0; + int lowest = 0; + int i, j, pos; + + for (i = 0; i <= blocksize * 2; i++) { + // We use a width of 16 here to match the libavcodec sad functions + for (j = 0; i <= 15; i++) { + pos = (y - i) * stride + (x - j); + if (src[pos] < lowest) + lowest = src[pos]; + else if (src[pos] > highest) { + highest = src[pos]; + } + } + } + + return highest - lowest; +} + +/** + * Find the rotation for a given block. + */ +static double block_angle(int x, int y, int cx, int cy, IntMotionVector *shift) +{ + double a1, a2, diff; + + a1 = atan2(y - cy, x - cx); + a2 = atan2(y - cy + shift->y, x - cx + shift->x); + + diff = a2 - a1; + + return (diff > M_PI) ? diff - 2 * M_PI : + (diff < -M_PI) ? diff + 2 * M_PI : + diff; +} + +/** + * 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). + */ +static void find_motion(DeshakeContext *deshake, uint8_t *src1, uint8_t *src2, + int width, int height, int stride, Transform *t) +{ + int x, y; + IntMotionVector mv = {0, 0}; + int counts[128][128]; + int count_max_value = 0; + int contrast; + + int pos; + double *angles = av_malloc(sizeof(*angles) * width * height / (16 * deshake->blocksize)); + int center_x = 0, center_y = 0; + double p_x, p_y; + + // Reset counts to zero + for (x = 0; x < deshake->rx * 2 + 1; x++) { + for (y = 0; y < deshake->ry * 2 + 1; y++) { + counts[x][y] = 0; + } + } + + pos = 0; + // Find motion for every block and store the motion vector in the counts + for (y = deshake->ry; y < height - deshake->ry - (deshake->blocksize * 2); y += deshake->blocksize * 2) { + // We use a width of 16 here to match the libavcodec sad functions + for (x = deshake->rx; x < width - deshake->rx - 16; x += 16) { + // If the contrast is too low, just skip this block as it probably + // won't be very useful to us. + contrast = block_contrast(src2, x, y, stride, deshake->blocksize); + if (contrast > deshake->contrast) { + //av_log(NULL, AV_LOG_ERROR, "%d\n", contrast); + find_block_motion(deshake, src1, src2, x, y, stride, &mv); + if (mv.x != -1 && mv.y != -1) { + counts[mv.x + deshake->rx][mv.y + deshake->ry] += 1; + if (x > deshake->rx && y > deshake->ry) + angles[pos++] = block_angle(x, y, 0, 0, &mv); + + center_x += mv.x; + center_y += mv.y; + } + } + } + } + + if (pos) { + center_x /= pos; + center_y /= pos; + t->angle = clean_mean(angles, pos); + if (t->angle < 0.001) + t->angle = 0; + } else { + t->angle = 0; + } + + // Find the most common motion vector in the frame and use it as the gmv + for (y = deshake->ry * 2; y >= 0; y--) { + for (x = 0; x < deshake->rx * 2 + 1; x++) { + //av_log(NULL, AV_LOG_ERROR, "%5d ", counts[x][y]); + if (counts[x][y] > count_max_value) { + t->vector.x = x - deshake->rx; + t->vector.y = y - deshake->ry; + count_max_value = counts[x][y]; + } + } + //av_log(NULL, AV_LOG_ERROR, "\n"); + } + + p_x = (center_x - width / 2); + p_y = (center_y - height / 2); + t->vector.x += (cos(t->angle)-1)*p_x - sin(t->angle)*p_y; + t->vector.y += sin(t->angle)*p_x + (cos(t->angle)-1)*p_y; + + // Clamp max shift & rotation? + t->vector.x = av_clipf(t->vector.x, -deshake->rx * 2, deshake->rx * 2); + t->vector.y = av_clipf(t->vector.y, -deshake->ry * 2, deshake->ry * 2); + t->angle = av_clipf(t->angle, -0.1, 0.1); + + //av_log(NULL, AV_LOG_ERROR, "%d x %d\n", avg->x, avg->y); + av_free(angles); +} + +static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque) +{ + DeshakeContext *deshake = ctx->priv; + char filename[256] = {0}; + + deshake->rx = 16; + deshake->ry = 16; + deshake->edge = FILL_MIRROR; + deshake->blocksize = 8; + deshake->contrast = 125; + deshake->search = EXHAUSTIVE; + deshake->refcount = 20; + + deshake->cw = -1; + deshake->ch = -1; + deshake->cx = -1; + deshake->cy = -1; + + if (args) { + sscanf(args, "%d:%d:%d:%d:%d:%d:%d:%d:%d:%d:%255s", + &deshake->cx, &deshake->cy, &deshake->cw, &deshake->ch, + &deshake->rx, &deshake->ry, (int *)&deshake->edge, + &deshake->blocksize, &deshake->contrast, (int *)&deshake->search, filename); + + deshake->blocksize /= 2; + + deshake->rx = av_clip(deshake->rx, 0, 64); + deshake->ry = av_clip(deshake->ry, 0, 64); + deshake->edge = av_clip(deshake->edge, FILL_BLANK, FILL_COUNT - 1); + deshake->blocksize = av_clip(deshake->blocksize, 4, 128); + deshake->contrast = av_clip(deshake->contrast, 1, 255); + deshake->search = av_clip(deshake->search, EXHAUSTIVE, SEARCH_COUNT - 1); + + } + if (*filename) + deshake->fp = fopen(filename, "w"); + if (deshake->fp) + fwrite("Ori x, Avg x, Fin x, Ori y, Avg y, Fin y, Ori angle, Avg angle, Fin angle, Ori zoom, Avg zoom, Fin zoom\n", sizeof(char), 104, deshake->fp); + + // Quadword align left edge of box for MMX code, adjust width if necessary + // to keep right margin + if (deshake->cx > 0) { + deshake->cw += deshake->cx - (deshake->cx & ~15); + deshake->cx &= ~15; + } + + av_log(ctx, AV_LOG_INFO, "cx: %d, cy: %d, cw: %d, ch: %d, rx: %d, ry: %d, edge: %d blocksize: %d contrast: %d search: %d\n", + deshake->cx, deshake->cy, deshake->cw, deshake->ch, + deshake->rx, deshake->ry, deshake->edge, deshake->blocksize * 2, deshake->contrast, deshake->search); + + return 0; +} + +static int query_formats(AVFilterContext *ctx) +{ + enum PixelFormat pix_fmts[] = { + PIX_FMT_YUV420P, PIX_FMT_YUV422P, PIX_FMT_YUV444P, PIX_FMT_YUV410P, + PIX_FMT_YUV411P, PIX_FMT_YUV440P, PIX_FMT_YUVJ420P, PIX_FMT_YUVJ422P, + PIX_FMT_YUVJ444P, PIX_FMT_YUVJ440P, PIX_FMT_NONE + }; + + avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts)); + + return 0; +} + +static int config_props(AVFilterLink *link) +{ + DeshakeContext *deshake = link->dst->priv; + + deshake->ref = NULL; + deshake->last.vector.x = 0; + deshake->last.vector.y = 0; + deshake->last.angle = 0; + deshake->last.zoom = 0; + + deshake->avctx = avcodec_alloc_context3(NULL); + dsputil_init(&deshake->c, deshake->avctx); + + return 0; +} + +static av_cold void uninit(AVFilterContext *ctx) +{ + DeshakeContext *deshake = ctx->priv; + + avfilter_unref_buffer(deshake->ref); + if (deshake->fp) + fclose(deshake->fp); +} + +static void end_frame(AVFilterLink *link) +{ + DeshakeContext *deshake = link->dst->priv; + AVFilterBufferRef *in = link->cur_buf; + AVFilterBufferRef *out = link->dst->outputs[0]->out_buf; + Transform t = {{0},0}, orig = {{0},0}; + float matrix[9]; + float alpha = 2.0 / deshake->refcount; + char tmp[256]; + + if (deshake->cx < 0 || deshake->cy < 0 || deshake->cw < 0 || deshake->ch < 0) { + // Find the most likely global motion for the current frame + find_motion(deshake, (deshake->ref == NULL) ? in->data[0] : deshake->ref->data[0], in->data[0], link->w, link->h, in->linesize[0], &t); + } else { + uint8_t *src1 = (deshake->ref == NULL) ? in->data[0] : deshake->ref->data[0]; + uint8_t *src2 = in->data[0]; + + deshake->cx = FFMIN(deshake->cx, link->w); + deshake->cy = FFMIN(deshake->cy, link->h); + + if ((unsigned)deshake->cx + (unsigned)deshake->cw > link->w) deshake->cw = link->w - deshake->cx; + if ((unsigned)deshake->cy + (unsigned)deshake->ch > link->h) deshake->ch = link->h - deshake->cy; + + // Quadword align right margin + deshake->cw &= ~15; + + src1 += deshake->cy * in->linesize[0] + deshake->cx; + src2 += deshake->cy * in->linesize[0] + deshake->cx; + + find_motion(deshake, src1, src2, deshake->cw, deshake->ch, in->linesize[0], &t); + } + + + // Copy transform so we can output it later to compare to the smoothed value + orig.vector.x = t.vector.x; + orig.vector.y = t.vector.y; + orig.angle = t.angle; + orig.zoom = t.zoom; + + // Generate a one-sided moving exponential average + deshake->avg.vector.x = alpha * t.vector.x + (1.0 - alpha) * deshake->avg.vector.x; + deshake->avg.vector.y = alpha * t.vector.y + (1.0 - alpha) * deshake->avg.vector.y; + deshake->avg.angle = alpha * t.angle + (1.0 - alpha) * deshake->avg.angle; + deshake->avg.zoom = alpha * t.zoom + (1.0 - alpha) * deshake->avg.zoom; + + // Remove the average from the current motion to detect the motion that + // is not on purpose, just as jitter from bumping the camera + t.vector.x -= deshake->avg.vector.x; + t.vector.y -= deshake->avg.vector.y; + t.angle -= deshake->avg.angle; + t.zoom -= deshake->avg.zoom; + + // Invert the motion to undo it + t.vector.x *= -1; + t.vector.y *= -1; + t.angle *= -1; + + // Write statistics to file + if (deshake->fp) { + snprintf(tmp, 256, "%f, %f, %f, %f, %f, %f, %f, %f, %f, %f, %f, %f\n", orig.vector.x, deshake->avg.vector.x, t.vector.x, orig.vector.y, deshake->avg.vector.y, t.vector.y, orig.angle, deshake->avg.angle, t.angle, orig.zoom, deshake->avg.zoom, t.zoom); + fwrite(tmp, sizeof(char), strlen(tmp), deshake->fp); + } + + // Turn relative current frame motion into absolute by adding it to the + // last absolute motion + t.vector.x += deshake->last.vector.x; + t.vector.y += deshake->last.vector.y; + t.angle += deshake->last.angle; + t.zoom += deshake->last.zoom; + + // Shrink motion by 10% to keep things centered in the camera frame + t.vector.x *= 0.9; + t.vector.y *= 0.9; + t.angle *= 0.9; + + // Store the last absolute motion information + deshake->last.vector.x = t.vector.x; + deshake->last.vector.y = t.vector.y; + deshake->last.angle = t.angle; + deshake->last.zoom = t.zoom; + + // Generate a luma transformation matrix + avfilter_get_matrix(t.vector.x, t.vector.y, t.angle, 1.0 + t.zoom / 100.0, matrix); + + // Transform the luma plane + avfilter_transform(in->data[0], out->data[0], in->linesize[0], out->linesize[0], link->w, link->h, matrix, INTERPOLATE_BILINEAR, deshake->edge); + + // Generate a chroma transformation matrix + avfilter_get_matrix(t.vector.x / (link->w / CHROMA_WIDTH(link)), t.vector.y / (link->h / CHROMA_HEIGHT(link)), t.angle, 1.0 + t.zoom / 100.0, matrix); + + // Transform the chroma planes + avfilter_transform(in->data[1], out->data[1], in->linesize[1], out->linesize[1], CHROMA_WIDTH(link), CHROMA_HEIGHT(link), matrix, INTERPOLATE_BILINEAR, deshake->edge); + avfilter_transform(in->data[2], out->data[2], in->linesize[2], out->linesize[2], CHROMA_WIDTH(link), CHROMA_HEIGHT(link), matrix, INTERPOLATE_BILINEAR, deshake->edge); + + // Store the current frame as the reference frame for calculating the + // motion of the next frame + if (deshake->ref != NULL) + avfilter_unref_buffer(deshake->ref); + + // Cleanup the old reference frame + deshake->ref = in; + + // Draw the transformed frame information + avfilter_draw_slice(link->dst->outputs[0], 0, link->h, 1); + avfilter_end_frame(link->dst->outputs[0]); + avfilter_unref_buffer(out); +} + +static void draw_slice(AVFilterLink *link, int y, int h, int slice_dir) +{ +} + +AVFilter avfilter_vf_deshake = { + .name = "deshake", + .description = NULL_IF_CONFIG_SMALL("Stabilize shaky video."), + + .priv_size = sizeof(DeshakeContext), + + .init = init, + .uninit = uninit, + .query_formats = query_formats, + + .inputs = (const AVFilterPad[]) {{ .name = "default", + .type = AVMEDIA_TYPE_VIDEO, + .draw_slice = draw_slice, + .end_frame = end_frame, + .config_props = config_props, + .min_perms = AV_PERM_READ, }, + { .name = NULL}}, + + .outputs = (const AVFilterPad[]) {{ .name = "default", + .type = AVMEDIA_TYPE_VIDEO, }, + { .name = NULL}}, +}; |
