diff --git a/doc/filters.texi b/doc/filters.texi index 527c6a08b2..8c5d3a5760 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -15348,42 +15348,16 @@ Set the line to start scanning for EIA-608 data. Default is @code{0}. @item scan_max Set the line to end scanning for EIA-608 data. Default is @code{29}. -@item mac -Set minimal acceptable amplitude change for sync codes detection. -Default is @code{0.2}. Allowed range is @code{[0.001 - 1]}. - @item spw Set the ratio of width reserved for sync code detection. -Default is @code{0.27}. Allowed range is @code{[0.01 - 0.7]}. - -@item mhd -Set the max peaks height difference for sync code detection. -Default is @code{0.1}. Allowed range is @code{[0.0 - 0.5]}. - -@item mpd -Set max peaks period difference for sync code detection. -Default is @code{0.1}. Allowed range is @code{[0.0 - 0.5]}. - -@item msd -Set the first two max start code bits differences. -Default is @code{0.02}. Allowed range is @code{[0.0 - 0.5]}. - -@item bhd -Set the minimum ratio of bits height compared to 3rd start code bit. -Default is @code{0.75}. Allowed range is @code{[0.01 - 1]}. - -@item th_w -Set the white color threshold. Default is @code{0.35}. Allowed range is @code{[0.1 - 1]}. - -@item th_b -Set the black color threshold. Default is @code{0.15}. Allowed range is @code{[0.0 - 0.5]}. +Default is @code{0.27}. Allowed range is @code{[0.1 - 0.7]}. @item chp Enable checking the parity bit. In the event of a parity error, the filter will output @code{0x00} for that character. Default is false. @item lp -Lowpass lines prior to further processing. Default is disabled. +Lowpass lines prior to further processing. Default is enabled. @end table @subsection Examples diff --git a/libavfilter/vf_readeia608.c b/libavfilter/vf_readeia608.c index 27a0c58321..0ddc7bfd50 100644 --- a/libavfilter/vf_readeia608.c +++ b/libavfilter/vf_readeia608.c @@ -36,41 +36,45 @@ #include "internal.h" #include "video.h" -#define FALL 0 -#define RISE 1 +#define LAG 25 +#define SYNC_MIN 12.f +#define SYNC_MAX 15.f + +typedef struct CodeItem { + uint8_t bit; + int size; +} CodeItem; typedef struct ReadEIA608Context { const AVClass *class; int start, end; - int min_range; - int max_peak_diff; - int max_period_diff; - int max_start_diff; int nb_found; int white; int black; - float mpd, mhd, msd, mac, spw, bhd, wth, bth; + float spw; int chp; int lp; + + uint64_t histogram[256]; + uint8_t *temp; + uint8_t *signal; + CodeItem *code; + float *unfiltered; + float *filtered; + float *avg_filter; + float *std_filter; } ReadEIA608Context; #define OFFSET(x) offsetof(ReadEIA608Context, x) #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM static const AVOption readeia608_options[] = { - { "scan_min", "set from which line to scan for codes", OFFSET(start), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS }, - { "scan_max", "set to which line to scan for codes", OFFSET(end), AV_OPT_TYPE_INT, {.i64=29}, 0, INT_MAX, FLAGS }, - { "mac", "set minimal acceptable amplitude change for sync codes detection", OFFSET(mac), AV_OPT_TYPE_FLOAT, {.dbl=.2}, 0.001, 1, FLAGS }, - { "spw", "set ratio of width reserved for sync code detection", OFFSET(spw), AV_OPT_TYPE_FLOAT, {.dbl=.27}, 0.1, 0.7, FLAGS }, - { "mhd", "set max peaks height difference for sync code detection", OFFSET(mhd), AV_OPT_TYPE_FLOAT, {.dbl=.1}, 0, 0.5, FLAGS }, - { "mpd", "set max peaks period difference for sync code detection", OFFSET(mpd), AV_OPT_TYPE_FLOAT, {.dbl=.1}, 0, 0.5, FLAGS }, - { "msd", "set first two max start code bits differences", OFFSET(msd), AV_OPT_TYPE_FLOAT, {.dbl=.02}, 0, 0.5, FLAGS }, - { "bhd", "set min ratio of bits height compared to 3rd start code bit", OFFSET(bhd), AV_OPT_TYPE_FLOAT, {.dbl=.75}, 0.01, 1, FLAGS }, - { "th_w", "set white color threshold", OFFSET(wth), AV_OPT_TYPE_FLOAT, {.dbl=.35}, 0.1, 1, FLAGS }, - { "th_b", "set black color threshold", OFFSET(bth), AV_OPT_TYPE_FLOAT, {.dbl=.15}, 0, 0.5, FLAGS }, - { "chp", "check and apply parity bit", OFFSET(chp), AV_OPT_TYPE_BOOL, {.i64= 0}, 0, 1, FLAGS }, - { "lp", "lowpass line prior to processing", OFFSET(lp), AV_OPT_TYPE_BOOL, {.i64= 0}, 0, 1, FLAGS }, + { "scan_min", "set from which line to scan for codes", OFFSET(start), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS }, + { "scan_max", "set to which line to scan for codes", OFFSET(end), AV_OPT_TYPE_INT, {.i64=29}, 0, INT_MAX, FLAGS }, + { "spw", "set ratio of width reserved for sync code detection", OFFSET(spw), AV_OPT_TYPE_FLOAT, {.dbl=.27}, 0.1, 0.7, FLAGS }, + { "chp", "check and apply parity bit", OFFSET(chp), AV_OPT_TYPE_BOOL, {.i64= 0}, 0, 1, FLAGS }, + { "lp", "lowpass line prior to processing", OFFSET(lp), AV_OPT_TYPE_BOOL, {.i64= 1}, 0, 1, FLAGS }, { NULL } }; @@ -96,10 +100,9 @@ static int query_formats(AVFilterContext *ctx) static int config_input(AVFilterLink *inlink) { - const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format); AVFilterContext *ctx = inlink->dst; ReadEIA608Context *s = ctx->priv; - int depth = desc->comp[0].depth; + int size = inlink->w + LAG; if (s->end >= inlink->h) { av_log(ctx, AV_LOG_WARNING, "Last line to scan too large, clipping.\n"); @@ -111,34 +114,177 @@ static int config_input(AVFilterLink *inlink) return AVERROR(EINVAL); } - s->min_range = s->mac * ((1 << depth) - 1); - s->max_peak_diff = s->mhd * ((1 << depth) - 1); - s->max_period_diff = s->mpd * ((1 << depth) - 1); - s->max_start_diff = s->msd * ((1 << depth) - 1); - s->white = s->wth * ((1 << depth) - 1); - s->black = s->bth * ((1 << depth) - 1); - s->temp = av_calloc(inlink->w, sizeof(*s->temp)); + 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->code = av_calloc(size, sizeof(*s->code)); + s->temp = av_calloc(size, sizeof(*s->temp)); if (!s->temp) return AVERROR(ENOMEM); return 0; } +static void build_histogram(ReadEIA608Context *s, const uint8_t *src, int len) +{ + memset(s->histogram, 0, sizeof(s->histogram)); + + for (int i = 0; i < len; i++) + s->histogram[src[i]]++; +} + +static void find_black_and_white(ReadEIA608Context *s) +{ + int start = 0, end = 0, middle; + int black = 0, white = 0; + int cnt; + + for (int i = 0; i < 256; i++) { + if (s->histogram[i]) { + start = i; + break; + } + } + + for (int i = 255; i >= 0; i--) { + if (s->histogram[i]) { + end = i; + break; + } + } + + middle = start + (end - start) / 2; + + cnt = 0; + for (int i = start; i <= middle; i++) { + if (s->histogram[i] > cnt) { + cnt = s->histogram[i]; + black = i; + } + } + + cnt = 0; + for (int i = end; i >= middle; i--) { + if (s->histogram[i] > cnt) { + cnt = s->histogram[i]; + white = i; + } + } + + s->black = black; + s->white = white; +} + +static float meanf(float *data, int len) +{ + float sum = 0.0, mean = 0.0; + + for (int i = 0; i < len; i++) + sum += data[i]; + + mean = sum / len; + + return mean; +} + +static float stddevf(float *data, int len) +{ + float m = meanf(data, len); + float standard_deviation = 0.f; + + for (int i = 0; i < len; i++) + standard_deviation += (data[i] - m) * (data[i] - 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, + 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]; + } + + for (int i = 0; i < lag; i++) { + unfiltered[i] = meanf(unfiltered, len * s->spw); + filtered[i] = unfiltered[i]; + } + + memset(signal, 0, len); + + avg_filter[lag - 1] = meanf(unfiltered, lag); + std_filter[lag - 1] = stddevf(unfiltered, 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; + } else { + signal[i - lag] = 0; + } + filtered[i] = influence * unfiltered[i] + (1.f - influence) * filtered[i-1]; + } 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); + + signal[i - lag] = distance_from_black <= distance_from_white ? 0 : 255; + } + avg_filter[i] = meanf(filtered + i - lag, lag); + std_filter[i] = stddevf(filtered + i - lag, lag); + } +} + +static int periods(const uint8_t *signal, CodeItem *code, int len) +{ + int hold = signal[0], cnt = 0; + int last = 0; + + memset(code, 0, len * sizeof(*code)); + + for (int i = 1; i < len; i++) { + if (signal[i] != hold) { + code[cnt].size = i - last; + code[cnt].bit = hold; + hold = signal[i]; + last = i; + cnt++; + } + } + + code[cnt].size = len - last; + code[cnt].bit = hold; + + return cnt + 1; +} + +static void dump_code(AVFilterContext *ctx, int len, int item) +{ + ReadEIA608Context *s = ctx->priv; + + av_log(ctx, AV_LOG_DEBUG, "%d:", item); + for (int i = 0; i < len; i++) { + av_log(ctx, AV_LOG_DEBUG, " %03d", s->code[i].size); + } + av_log(ctx, AV_LOG_DEBUG, "\n"); +} + static void extract_line(AVFilterContext *ctx, AVFilterLink *inlink, AVFrame *in, int line) { ReadEIA608Context *s = ctx->priv; - int max = 0, min = INT_MAX; - int i, ch, range = 0; + int i, j, ch, len; const uint8_t *src; - uint16_t clock[8][2] = { { 0 } }; - const int sync_width = s->spw * in->width; - int last = 0, peaks = 0, max_peak_diff = 0, dir = RISE; - const int width_per_bit = (in->width - sync_width) / 19; uint8_t byte[2] = { 0 }; - int s1, s2, s3, parity; + uint8_t codes[19] = { 0 }; + 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; @@ -157,78 +303,60 @@ static void extract_line(AVFilterContext *ctx, AVFilterLink *inlink, AVFrame *in src = s->temp; } - for (i = 0; i < sync_width; i++) { - max = FFMAX(max, src[i]); - min = FFMIN(min, src[i]); - } - - range = max - min; - if (range < s->min_range) + build_histogram(s, src, inlink->w); + find_black_and_white(s); + if (s->white - s->black < 5) return; - for (i = 0; i < sync_width; i++) { - int Y = src[i]; + 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); + 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) { + return; + } - if (dir == RISE) { - if (Y < last) { - dir = FALL; - if (last >= s->white) { - clock[peaks][0] = last; - clock[peaks][1] = i; - peaks++; - if (peaks > 7) - break; - } - } - } else if (dir == FALL) { - if (Y > last && last <= s->black) { - dir = RISE; - } + for (i = 14; i < len; i++) { + bit_size += s->code[i].size; + } + + bit_size /= 19.f; + for (i = 1; i < 14; i++) { + if (s->code[i].size > bit_size * 1.5f) { + return; } - last = Y; } - if (peaks != 7) { - av_log(ctx, AV_LOG_DEBUG, "peaks: %d != 7\n", peaks); + if (s->code[15].size / bit_size < 0.45f) { return; } - for (i = 1; i < 7; i++) - max_peak_diff = FFMAX(max_peak_diff, FFABS(clock[i][0] - clock[i-1][0])); + for (j = 0, i = 14; i < len; i++) { + int run, bit; - if (max_peak_diff > s->max_peak_diff) { - av_log(ctx, AV_LOG_DEBUG, "mhd: %d > %d\n", max_peak_diff, s->max_peak_diff); - return; - } + run = lrintf(s->code[i].size / bit_size); + bit = s->code[i].bit; - max = 0; min = INT_MAX; - for (i = 1; i < 7; i++) { - max = FFMAX(max, FFABS(clock[i][1] - clock[i-1][1])); - min = FFMIN(min, FFABS(clock[i][1] - clock[i-1][1])); - } + for (int k = 0; j < 19 && k < run; k++) { + codes[j++] = bit; + } - range = max - min; - if (range > s->max_period_diff) { - av_log(ctx, AV_LOG_DEBUG, "mpd: %d > %d\n", range, s->max_period_diff); - return; - } - - s1 = src[sync_width + width_per_bit * 0 + width_per_bit / 2]; - s2 = src[sync_width + width_per_bit * 1 + width_per_bit / 2]; - s3 = src[sync_width + width_per_bit * 2 + width_per_bit / 2]; - - if (FFABS(s1 - s2) > s->max_start_diff || s1 > s->black || s2 > s->black || s3 < s->white) { - av_log(ctx, AV_LOG_DEBUG, "msd: %d > %d\n", FFABS(s1 - s2), s->max_start_diff); - return; + if (j >= 19) + break; } for (ch = 0; ch < 2; ch++) { for (parity = 0, i = 0; i < 8; i++) { - int b = src[sync_width + width_per_bit * (i + 3 + 8 * ch) + width_per_bit / 2]; + int b = codes[3 + ch * 8 + i]; - if (b - s1 > (s3 - s1) * s->bhd) { - b = 1; + if (b == 255) { parity++; + b = 1; } else { b = 0; } @@ -245,6 +373,10 @@ static void extract_line(AVFilterContext *ctx, AVFilterLink *inlink, AVFrame *in { uint8_t key[128], value[128]; + //snprintf(key, sizeof(key), "lavfi.readeia608.%d.bits", s->nb_found); + //snprintf(value, sizeof(value), "0b%d%d%d%d%d%d%d%d 0b%d%d%d%d%d%d%d%d", codes[3]==255,codes[4]==255,codes[5]==255,codes[6]==255,codes[7]==255,codes[8]==255,codes[9]==255,codes[10]==255,codes[11]==255,codes[12]==255,codes[13]==255,codes[14]==255,codes[15]==255,codes[16]==255,codes[17]==255,codes[18]==255); + //av_dict_set(&in->metadata, key, value, 0); + snprintf(key, sizeof(key), "lavfi.readeia608.%d.cc", s->nb_found); snprintf(value, sizeof(value), "0x%02X%02X", byte[0], byte[1]); av_dict_set(&in->metadata, key, value, 0); @@ -276,6 +408,12 @@ 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); } static const AVFilterPad readeia608_inputs[] = {