gstreamer/subprojects/gst-plugins-bad/sys/dwrite/libcaption/caption.c
2023-06-27 13:23:07 +00:00

529 lines
16 KiB
C

/**********************************************************************************************/
/* The MIT License */
/* */
/* Copyright 2016-2017 Twitch Interactive, Inc. or its affiliates. All Rights Reserved. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining a copy */
/* of this software and associated documentation files (the "Software"), to deal */
/* in the Software without restriction, including without limitation the rights */
/* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell */
/* copies of the Software, and to permit persons to whom the Software is */
/* furnished to do so, subject to the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be included in */
/* all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR */
/* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, */
/* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE */
/* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER */
/* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, */
/* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN */
/* THE SOFTWARE. */
/**********************************************************************************************/
#include "caption.h"
#include "eia608.h"
#include "utf8.h"
#include "xds.h"
#include <stdio.h>
#include <string.h>
////////////////////////////////////////////////////////////////////////////////
void
caption_frame_buffer_clear (caption_frame_buffer_t * buff)
{
memset (buff, 0, sizeof (caption_frame_buffer_t));
}
void
caption_frame_state_clear (caption_frame_t * frame)
{
frame->write = 0;
frame->timestamp = -1;
frame->state = (caption_frame_state_t) {
0, 0, 0, SCREEN_ROWS - 1, 0, 0}; // clear global state
}
void
caption_frame_init (caption_frame_t * frame)
{
xds_init (&frame->xds);
caption_frame_state_clear (frame);
caption_frame_buffer_clear (&frame->back);
caption_frame_buffer_clear (&frame->front);
}
////////////////////////////////////////////////////////////////////////////////
// Helpers
static caption_frame_cell_t *
frame_buffer_cell (caption_frame_buffer_t * buff, int row, int col)
{
if (!buff || 0 > row || SCREEN_ROWS <= row || 0 > col || SCREEN_COLS <= col) {
return 0;
}
return &buff->cell[row][col];
}
int caption_frame_clear_char (caption_frame_t * frame, int row, int col)
{
if (!frame->write) {
return 0;
}
caption_frame_cell_t *cell = frame_buffer_cell (frame->write, row, col);
if (cell) {
memset (cell, 0, sizeof (caption_frame_cell_t));
return 1;
}
return 0;
}
uint16_t _eia608_from_utf8 (const char *s); // function is in eia608.c.re2c
int
caption_frame_write_char (caption_frame_t * frame, int row, int col,
eia608_style_t style, int underline, const char *c)
{
if (!frame->write || !_eia608_from_utf8 (c)) {
return 0;
}
caption_frame_cell_t *cell = frame_buffer_cell (frame->write, row, col);
if (cell && utf8_char_copy (&cell->data[0], c)) {
cell->uln = underline;
cell->sty = style;
return 1;
}
return 0;
}
const utf8_char_t *
caption_frame_read_char (caption_frame_t * frame, int row, int col,
eia608_style_t * style, int *underline)
{
// always read from front
caption_frame_cell_t *cell = frame_buffer_cell (&frame->front, row, col);
if (!cell) {
if (style) {
(*style) = eia608_style_white;
}
if (underline) {
(*underline) = 0;
}
return EIA608_CHAR_NULL;
}
if (style) {
(*style) = cell->sty;
}
if (underline) {
(*underline) = cell->uln;
}
return &cell->data[0];
}
////////////////////////////////////////////////////////////////////////////////
// Parsing
libcaption_stauts_t
caption_frame_carriage_return (caption_frame_t * frame)
{
if (0 > frame->state.row || SCREEN_ROWS <= frame->state.row) {
return LIBCAPTION_ERROR;
}
int r = frame->state.row - (frame->state.rup - 1);
if (0 >= r || !caption_frame_rollup (frame)) {
return LIBCAPTION_OK;
}
for (; r < SCREEN_ROWS; ++r) {
uint8_t *dst = (uint8_t *) frame_buffer_cell (frame->write, r - 1, 0);
uint8_t *src = (uint8_t *) frame_buffer_cell (frame->write, r - 0, 0);
memcpy (dst, src, sizeof (caption_frame_cell_t) * SCREEN_COLS);
}
frame->state.col = 0;
caption_frame_cell_t *cell =
frame_buffer_cell (frame->write, SCREEN_ROWS - 1, 0);
memset (cell, 0, sizeof (caption_frame_cell_t) * SCREEN_COLS);
return LIBCAPTION_OK;
}
////////////////////////////////////////////////////////////////////////////////
libcaption_stauts_t
eia608_write_char (caption_frame_t * frame, char *c)
{
if (0 == c || 0 == c[0] || SCREEN_ROWS <= frame->state.row
|| 0 > frame->state.row || SCREEN_COLS <= frame->state.col
|| 0 > frame->state.col) {
// NO-OP
} else if (caption_frame_write_char (frame, frame->state.row,
frame->state.col, frame->state.sty, frame->state.uln, c)) {
frame->state.col += 1;
}
return LIBCAPTION_OK;
}
libcaption_stauts_t
caption_frame_end (caption_frame_t * frame)
{
memcpy (&frame->front, &frame->back, sizeof (caption_frame_buffer_t));
caption_frame_buffer_clear (&frame->back); // This is required
return LIBCAPTION_READY;
}
libcaption_stauts_t
caption_frame_decode_preamble (caption_frame_t * frame, uint16_t cc_data)
{
eia608_style_t sty;
int row, col, chn, uln;
if (eia608_parse_preamble (cc_data, &row, &col, &sty, &chn, &uln)) {
frame->state.row = row;
frame->state.col = col;
frame->state.sty = sty;
frame->state.uln = uln;
}
return LIBCAPTION_OK;
}
libcaption_stauts_t
caption_frame_decode_midrowchange (caption_frame_t * frame, uint16_t cc_data)
{
eia608_style_t sty;
int chn, unl;
if (eia608_parse_midrowchange (cc_data, &chn, &sty, &unl)) {
frame->state.sty = sty;
frame->state.uln = unl;
}
return LIBCAPTION_OK;
}
libcaption_stauts_t
caption_frame_backspace (caption_frame_t * frame)
{
// do not reverse wrap (tw 28:20)
frame->state.col = (0 < frame->state.col) ? (frame->state.col - 1) : 0;
caption_frame_clear_char (frame, frame->state.row, frame->state.col);
return LIBCAPTION_READY;
}
libcaption_stauts_t
caption_frame_delete_to_end_of_row (caption_frame_t * frame)
{
int c;
if (frame->write) {
for (c = frame->state.col; c < SCREEN_COLS; ++c) {
caption_frame_clear_char (frame, frame->state.row, c);
}
}
// TODO test this and replace loop
// uint8_t* dst = (uint8_t*)frame_buffer_cell(frame->write, frame->state.row, frame->state.col);
// memset(dst,0,sizeof(caption_frame_cell_t) * (SCREEN_COLS - frame->state.col - 1))
return LIBCAPTION_READY;
}
libcaption_stauts_t
caption_frame_decode_control (caption_frame_t * frame, uint16_t cc_data)
{
int cc;
eia608_control_t cmd = eia608_parse_control (cc_data, &cc);
switch (cmd) {
// PAINT ON
case eia608_control_resume_direct_captioning:
frame->state.rup = 0;
frame->write = &frame->front;
return LIBCAPTION_OK;
case eia608_control_erase_display_memory:
caption_frame_buffer_clear (&frame->front);
return LIBCAPTION_CLEAR;
// ROLL-UP
case eia608_control_roll_up_2:
frame->state.rup = 1;
frame->write = &frame->front;
return LIBCAPTION_OK;
case eia608_control_roll_up_3:
frame->state.rup = 2;
frame->write = &frame->front;
return LIBCAPTION_OK;
case eia608_control_roll_up_4:
frame->state.rup = 3;
frame->write = &frame->front;
return LIBCAPTION_OK;
case eia608_control_carriage_return:
return caption_frame_carriage_return (frame);
// Corrections (Is this only valid as part of paint on?)
case eia608_control_backspace:
return caption_frame_backspace (frame);
case eia608_control_delete_to_end_of_row:
return caption_frame_delete_to_end_of_row (frame);
// POP ON
case eia608_control_resume_caption_loading:
frame->state.rup = 0;
frame->write = &frame->back;
return LIBCAPTION_OK;
case eia608_control_erase_non_displayed_memory:
caption_frame_buffer_clear (&frame->back);
return LIBCAPTION_OK;
case eia608_control_end_of_caption:
return caption_frame_end (frame);
// cursor positioning
case eia608_tab_offset_0:
case eia608_tab_offset_1:
case eia608_tab_offset_2:
case eia608_tab_offset_3:
frame->state.col += (cmd - eia608_tab_offset_0);
return LIBCAPTION_OK;
// Unhandled
default:
case eia608_control_alarm_off:
case eia608_control_alarm_on:
case eia608_control_text_restart:
case eia608_control_text_resume_text_display:
return LIBCAPTION_OK;
}
}
libcaption_stauts_t
caption_frame_decode_text (caption_frame_t * frame, uint16_t cc_data)
{
int chan;
char char1[5], char2[5];
size_t chars = eia608_to_utf8 (cc_data, &chan, &char1[0], &char2[0]);
if (eia608_is_westeu (cc_data)) {
// Extended charcters replace the previous charcter for back compatibility
caption_frame_backspace (frame);
}
if (0 < chars) {
eia608_write_char (frame, char1);
}
if (1 < chars) {
eia608_write_char (frame, char2);
}
return LIBCAPTION_OK;
}
libcaption_stauts_t
caption_frame_decode (caption_frame_t * frame, uint16_t cc_data,
double timestamp)
{
if (!eia608_parity_varify (cc_data)) {
frame->status = LIBCAPTION_ERROR;
return frame->status;
}
if (eia608_is_padding (cc_data)) {
frame->status = LIBCAPTION_OK;
return frame->status;
}
// skip duplicate controll commands. We also skip duplicate specialna to match the behaviour of iOS/vlc
if ((eia608_is_specialna(cc_data) || eia608_is_control(cc_data)) && cc_data == frame->state.cc_data) {
if (timestamp < 0 && caption_frame_popon (frame))
frame->timestamp += (1 / 29.97);
return LIBCAPTION_OK;
}
if (timestamp >= 0) {
frame->timestamp = timestamp;
frame->status = LIBCAPTION_OK;
} else if (caption_frame_popon (frame)) {
frame->timestamp += (1 / 29.97);
}
frame->state.cc_data = cc_data;
if (frame->xds.state) {
frame->status = xds_decode (&frame->xds, cc_data);
} else if (eia608_is_xds (cc_data)) {
frame->status = xds_decode (&frame->xds, cc_data);
} else if (eia608_is_control (cc_data)) {
frame->status = caption_frame_decode_control (frame, cc_data);
} else if (eia608_is_basicna (cc_data) || eia608_is_specialna (cc_data)
|| eia608_is_westeu (cc_data)) {
// Don't decode text if we dont know what mode we are in.
if (!frame->write) {
frame->status = LIBCAPTION_OK;
return frame->status;
}
frame->status = caption_frame_decode_text (frame, cc_data);
// If we are in paint on mode, display immiditally
if (LIBCAPTION_OK == frame->status && caption_frame_painton (frame)) {
frame->status = LIBCAPTION_READY;
}
} else if (eia608_is_preamble (cc_data)) {
frame->status = caption_frame_decode_preamble (frame, cc_data);
} else if (eia608_is_midrowchange (cc_data)) {
frame->status = caption_frame_decode_midrowchange (frame, cc_data);
}
return frame->status;
}
////////////////////////////////////////////////////////////////////////////////
int
caption_frame_from_text (caption_frame_t * frame, const utf8_char_t * data)
{
ssize_t size = (ssize_t) strlen (data);
caption_frame_init (frame);
frame->write = &frame->back;
for (size_t r = 0; (*data) && size && r < SCREEN_ROWS;) {
// skip whitespace at start of line
while (size && utf8_char_whitespace (data)) {
size_t s = utf8_char_length (data);
data += s, size -= s;
}
// get charcter count for wrap (or orest of line)
utf8_size_t char_count = utf8_wrap_length (data, SCREEN_COLS);
// write to caption frame
for (size_t c = 0; c < char_count; ++c) {
size_t char_length = utf8_char_length (data);
caption_frame_write_char (frame, r, c, eia608_style_white, 0, data);
data += char_length, size -= char_length;
}
r += char_count ? 1 : 0; // Update row num only if not blank
}
caption_frame_end (frame);
return 0;
}
////////////////////////////////////////////////////////////////////////////////
size_t
caption_frame_to_text (caption_frame_t * frame, utf8_char_t * data, int full)
{
int r, c, uln, crlf = 0, count = 0;
size_t s, size = 0;
eia608_style_t sty;
(*data) = '\0';
for (r = 0; r < SCREEN_ROWS; ++r) {
crlf += count, count = 0;
for (c = 0; c < SCREEN_COLS; ++c) {
const utf8_char_t *chr =
caption_frame_read_char (frame, r, c, &sty, &uln);
// dont start a new line until we encounter at least one printable character
if (full ||
(0 < utf8_char_length (chr) && (0 < count
|| !utf8_char_whitespace (chr)))) {
if (0 < crlf) {
memcpy (data, "\r\n\0", 3);
data += 2, size += 2, crlf = 0;
}
s = utf8_char_copy (data, chr);
data += s, size += s, ++count;
}
}
}
return size;
}
////////////////////////////////////////////////////////////////////////////////
size_t
caption_frame_dump_buffer (caption_frame_t * frame, utf8_char_t * buf)
{
int r, c;
size_t bytes, total = 0;
bytes =
sprintf (buf,
" timestamp: %f\n row: %02d col: %02d roll-up: %d\n",
frame->timestamp, frame->state.row, frame->state.col,
caption_frame_rollup (frame));
total += bytes, buf += bytes;
bytes =
sprintf (buf,
" 00000000001111111111222222222233\t 00000000001111111111222222222233\n"
" 01234567890123456789012345678901\t 01234567890123456789012345678901\n"
" %s--------------------------------%s\t %s--------------------------------%s\n",
EIA608_CHAR_BOX_DRAWINGS_LIGHT_DOWN_AND_RIGHT,
EIA608_CHAR_BOX_DRAWINGS_LIGHT_DOWN_AND_LEFT,
EIA608_CHAR_BOX_DRAWINGS_LIGHT_DOWN_AND_RIGHT,
EIA608_CHAR_BOX_DRAWINGS_LIGHT_DOWN_AND_LEFT);
total += bytes;
buf += bytes;
for (r = 0; r < SCREEN_ROWS; ++r) {
bytes = sprintf (buf, "%02d%s", r, EIA608_CHAR_VERTICAL_LINE);
total += bytes, buf += bytes;
// front buffer
for (c = 0; c < SCREEN_COLS; ++c) {
caption_frame_cell_t *cell = frame_buffer_cell (&frame->front, r, c);
bytes = utf8_char_copy (buf, (!cell
|| 0 == cell->data[0]) ? EIA608_CHAR_SPACE : &cell->data[0]);
total += bytes, buf += bytes;
}
bytes =
sprintf (buf, "%s\t%02d%s", EIA608_CHAR_VERTICAL_LINE, r,
EIA608_CHAR_VERTICAL_LINE);
total += bytes, buf += bytes;
// back buffer
for (c = 0; c < SCREEN_COLS; ++c) {
caption_frame_cell_t *cell = frame_buffer_cell (&frame->back, r, c);
bytes = utf8_char_copy (buf, (!cell
|| 0 == cell->data[0]) ? EIA608_CHAR_SPACE : &cell->data[0]);
total += bytes, buf += bytes;
}
bytes = sprintf (buf, "%s\n", EIA608_CHAR_VERTICAL_LINE);
total += bytes, buf += bytes;
}
bytes =
sprintf (buf,
" %s--------------------------------%s\t %s--------------------------------%s\n",
EIA608_CHAR_BOX_DRAWINGS_LIGHT_UP_AND_RIGHT,
EIA608_CHAR_BOX_DRAWINGS_LIGHT_UP_AND_LEFT,
EIA608_CHAR_BOX_DRAWINGS_LIGHT_UP_AND_RIGHT,
EIA608_CHAR_BOX_DRAWINGS_LIGHT_UP_AND_LEFT);
total += bytes, buf += bytes;
return total;
}
void
caption_frame_dump (caption_frame_t * frame)
{
utf8_char_t buff[CAPTION_FRAME_DUMP_BUF_SIZE];
caption_frame_dump_buffer (frame, buff);
fprintf (stderr, "%s\n", buff);
}