From 16968b619d9c0641591b6b115b28f4fbcf2037c9 Mon Sep 17 00:00:00 2001 From: Paul B Mahol Date: Mon, 23 Dec 2019 12:28:30 +0100 Subject: [PATCH] avfilter/vf_readeia608: use special struct to hold line items --- libavfilter/vf_readeia608.c | 148 +++++++++++++++++------------------- 1 file changed, 70 insertions(+), 78 deletions(-) diff --git a/libavfilter/vf_readeia608.c b/libavfilter/vf_readeia608.c index 43c57268fa..c36bcf5af9 100644 --- a/libavfilter/vf_readeia608.c +++ b/libavfilter/vf_readeia608.c @@ -40,6 +40,16 @@ #define SYNC_MIN 12.f #define SYNC_MAX 15.f +typedef struct LineItem { + int input; + int output; + + float unfiltered; + float filtered; + float average; + float deviation; +} LineItem; + typedef struct CodeItem { uint8_t bit; int size; @@ -57,13 +67,8 @@ typedef struct ReadEIA608Context { uint64_t histogram[256]; - uint8_t *temp; - uint8_t *signal; CodeItem *code; - float *unfiltered; - float *filtered; - float *avg_filter; - float *std_filter; + LineItem *line; } ReadEIA608Context; #define OFFSET(x) offsetof(ReadEIA608Context, x) @@ -114,26 +119,20 @@ static int config_input(AVFilterLink *inlink) return AVERROR(EINVAL); } - s->unfiltered = av_calloc(size, sizeof(*s->unfiltered)); - s->filtered = av_calloc(size, sizeof(*s->filtered)); - s->avg_filter = av_calloc(size, sizeof(*s->avg_filter)); - s->std_filter = av_calloc(size, sizeof(*s->std_filter)); - s->signal = av_calloc(size, sizeof(*s->signal)); + s->line = av_calloc(size, sizeof(*s->line)); s->code = av_calloc(size, sizeof(*s->code)); - s->temp = av_calloc(size, sizeof(*s->temp)); - if (!s->unfiltered || !s->filtered || !s->avg_filter || - !s->std_filter || !s->signal || !s->code || !s->temp) + if (!s->line || !s->code) return AVERROR(ENOMEM); return 0; } -static void build_histogram(ReadEIA608Context *s, const uint8_t *src, int len) +static void build_histogram(ReadEIA608Context *s, const LineItem *line, int len) { memset(s->histogram, 0, sizeof(s->histogram)); - for (int i = 0; i < len; i++) - s->histogram[src[i]]++; + for (int i = LAG; i < len + LAG; i++) + s->histogram[line[i].input]++; } static void find_black_and_white(ReadEIA608Context *s) @@ -178,87 +177,86 @@ static void find_black_and_white(ReadEIA608Context *s) s->white = white; } -static float meanf(float *data, int len) +static float meanf(const LineItem *line, int len) { float sum = 0.0, mean = 0.0; for (int i = 0; i < len; i++) - sum += data[i]; + sum += line[i].filtered; mean = sum / len; return mean; } -static float stddevf(float *data, int len) +static float stddevf(const LineItem *line, int len) { - float m = meanf(data, len); + float m = meanf(line, len); float standard_deviation = 0.f; for (int i = 0; i < len; i++) - standard_deviation += (data[i] - m) * (data[i] - m); + standard_deviation += (line[i].filtered - m) * (line[i].filtered - m); return sqrtf(standard_deviation / (len - 1)); } -static void thresholding(ReadEIA608Context *s, const uint8_t *y, uint8_t *signal, - float *unfiltered, float *filtered, float *avg_filter, float *std_filter, +static void thresholding(ReadEIA608Context *s, LineItem *line, int lag, float threshold, float influence, int len) { for (int i = lag; i < len + lag; i++) { - unfiltered[i] = y[i - lag] / 255.f; - filtered[i] = unfiltered[i]; + line[i].unfiltered = line[i].input / 255.f; + line[i].filtered = line[i].unfiltered; } for (int i = 0; i < lag; i++) { - unfiltered[i] = meanf(unfiltered, len * s->spw); - filtered[i] = unfiltered[i]; + line[i].unfiltered = meanf(line, len * s->spw); + line[i].filtered = line[i].unfiltered; } - memset(signal, 0, len); - - avg_filter[lag - 1] = meanf(unfiltered, lag); - std_filter[lag - 1] = stddevf(unfiltered, lag); + line[lag - 1].average = meanf(line, lag); + line[lag - 1].deviation = stddevf(line, lag); for (int i = lag; i < len + lag; i++) { - if (fabsf(unfiltered[i] - avg_filter[i-1]) > threshold * std_filter[i-1]) { - if (unfiltered[i] > avg_filter[i-1]) { - signal[i - lag] = 255; + if (fabsf(line[i].unfiltered - line[i-1].average) > threshold * line[i-1].deviation) { + if (line[i].unfiltered > line[i-1].average) { + line[i].output = 255; } else { - signal[i - lag] = 0; + line[i].output = 0; } - filtered[i] = influence * unfiltered[i] + (1.f - influence) * filtered[i-1]; + + line[i].filtered = influence * line[i].unfiltered + (1.f - influence) * line[i-1].filtered; } else { int distance_from_black, distance_from_white; - distance_from_black = FFABS(y[i - lag] - s->black); - distance_from_white = FFABS(y[i - lag] - s->white); + distance_from_black = FFABS(line[i].input - s->black); + distance_from_white = FFABS(line[i].input - s->white); - signal[i - lag] = distance_from_black <= distance_from_white ? 0 : 255; + line[i].output = distance_from_black <= distance_from_white ? 0 : 255; } - avg_filter[i] = meanf(filtered + i - lag, lag); - std_filter[i] = stddevf(filtered + i - lag, lag); + + line[i].average = meanf(line + i - lag, lag); + line[i].deviation = stddevf(line + i - lag, lag); } } -static int periods(const uint8_t *signal, CodeItem *code, int len) +static int periods(const LineItem *line, CodeItem *code, int len) { - int hold = signal[0], cnt = 0; - int last = 0; + int hold = line[LAG].output, cnt = 0; + int last = LAG; memset(code, 0, len * sizeof(*code)); - for (int i = 1; i < len; i++) { - if (signal[i] != hold) { + for (int i = LAG + 1; i < len + LAG; i++) { + if (line[i].output != hold) { code[cnt].size = i - last; code[cnt].bit = hold; - hold = signal[i]; + hold = line[i].output; last = i; cnt++; } } - code[cnt].size = len - last; + code[cnt].size = LAG + len - last; code[cnt].bit = hold; return cnt + 1; @@ -275,9 +273,10 @@ static void dump_code(AVFilterContext *ctx, int len, int item) av_log(ctx, AV_LOG_DEBUG, "\n"); } -static void extract_line(AVFilterContext *ctx, AVFilterLink *inlink, AVFrame *in, int line) +static void extract_line(AVFilterContext *ctx, AVFrame *in, int w, int nb_line) { ReadEIA608Context *s = ctx->priv; + LineItem *line = s->line; int i, j, ch, len; const uint8_t *src; uint8_t byte[2] = { 0 }; @@ -285,40 +284,38 @@ static void extract_line(AVFilterContext *ctx, AVFilterLink *inlink, AVFrame *in float bit_size = 0.f; int parity; - src = &in->data[0][line * in->linesize[0]]; - if (s->lp) { - uint8_t *dst = s->temp; - int w = inlink->w - 1; + memset(line, 0, (w + LAG) * sizeof(*line)); - for (i = 0; i < inlink->w; i++) { + src = &in->data[0][nb_line * in->linesize[0]]; + if (s->lp) { + for (i = 0; i < w; i++) { int a = FFMAX(i - 3, 0); int b = FFMAX(i - 2, 0); int c = FFMAX(i - 1, 0); - int d = FFMIN(i + 3, w); - int e = FFMIN(i + 2, w); - int f = FFMIN(i + 1, w); + int d = FFMIN(i + 3, w-1); + int e = FFMIN(i + 2, w-1); + int f = FFMIN(i + 1, w-1); - dst[i] = (src[a] + src[b] + src[c] + src[i] + src[d] + src[e] + src[f] + 6) / 7; + line[LAG + i].input = (src[a] + src[b] + src[c] + src[i] + src[d] + src[e] + src[f] + 6) / 7; + } + } else { + for (i = 0; i < w; i++) { + line[LAG + i].input = src[i]; } - - src = s->temp; } - build_histogram(s, src, inlink->w); + build_histogram(s, line, w); find_black_and_white(s); if (s->white - s->black < 5) return; - thresholding(s, src, s->signal, s->unfiltered, s->filtered, - s->avg_filter, s->std_filter, - LAG, 1, 0, inlink->w); - //memcpy(&in->data[0][line * in->linesize[0]], s->signal, inlink->w); - len = periods(s->signal, s->code, inlink->w); - dump_code(ctx, len, line); + thresholding(s, line, LAG, 1, 0, w); + len = periods(line, s->code, w); + dump_code(ctx, len, nb_line); if (len < 15 || s->code[14].bit != 0 || - inlink->w / (float)s->code[14].size < SYNC_MIN || - inlink->w / (float)s->code[14].size > SYNC_MAX) { + w / (float)s->code[14].size < SYNC_MIN || + w / (float)s->code[14].size > SYNC_MAX) { return; } @@ -383,7 +380,7 @@ static void extract_line(AVFilterContext *ctx, AVFilterLink *inlink, AVFrame *in av_dict_set(&in->metadata, key, value, 0); snprintf(key, sizeof(key), "lavfi.readeia608.%d.line", s->nb_found); - snprintf(value, sizeof(value), "%d", line); + snprintf(value, sizeof(value), "%d", nb_line); av_dict_set(&in->metadata, key, value, 0); } @@ -399,7 +396,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in) s->nb_found = 0; for (i = s->start; i <= s->end; i++) - extract_line(ctx, inlink, in, i); + extract_line(ctx, in, inlink->w, i); return ff_filter_frame(outlink, in); } @@ -408,13 +405,8 @@ static av_cold void uninit(AVFilterContext *ctx) { ReadEIA608Context *s = ctx->priv; - av_freep(&s->temp); av_freep(&s->code); - av_freep(&s->signal); - av_freep(&s->unfiltered); - av_freep(&s->filtered); - av_freep(&s->avg_filter); - av_freep(&s->std_filter); + av_freep(&s->line); } static const AVFilterPad readeia608_inputs[] = {