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-rw-r--r--libhb/decssasub.c381
1 files changed, 341 insertions, 40 deletions
diff --git a/libhb/decssasub.c b/libhb/decssasub.c
index 2b350dc47..99e4259a0 100644
--- a/libhb/decssasub.c
+++ b/libhb/decssasub.c
@@ -4,13 +4,19 @@
It may be used under the terms of the GNU General Public License. */
/*
- * Converts SSA subtitles to UTF-8 subtitles with limited HTML-style markup (<b>, <i>, <u>).
+ * Converts SSA subtitles to either:
+ * (1) TEXTSUB format: UTF-8 subtitles with limited HTML-style markup (<b>, <i>, <u>), or
+ * (2) PICTURESUB format, using libass.
*
* SSA format references:
* http://www.matroska.org/technical/specs/subtitles/ssa.html
* http://moodub.free.fr/video/ass-specs.doc
* vlc-1.0.4/modules/codec/subtitles/subsass.c:ParseSSAString
*
+ * libass references:
+ * libass-0.9.9/ass.h
+ * vlc-1.0.4/modules/codec/libass.c
+ *
* @author David Foster (davidfstr)
*/
@@ -18,6 +24,17 @@
#include <stdio.h>
#include "hb.h"
+#include <ass/ass.h>
+
+struct hb_work_private_s
+{
+ // If decoding to PICTURESUB format:
+ ASS_Library *ssa;
+ ASS_Renderer *renderer;
+ ASS_Track *ssaTrack;
+ int readOrder;
+};
+
typedef enum {
BOLD = 0x01,
ITALIC = 0x02,
@@ -92,14 +109,17 @@ static void ssa_append_html_tags_for_style_change(
#undef APPEND
}
-static hb_buffer_t *ssa_decode_to_utf8_line( uint8_t *in_data, int in_size );
+static hb_buffer_t *ssa_decode_line_to_utf8( uint8_t *in_data, int in_size, int in_sequence );
+static hb_buffer_t *ssa_decode_line_to_picture( hb_work_object_t * w, uint8_t *in_data, int in_size, int in_sequence );
/*
+ * Decodes a single SSA packet to one or more TEXTSUB or PICTURESUB subtitle packets.
+ *
* SSA packet format:
* ( Dialogue: Marked,Start,End,Style,Name,MarginL,MarginR,MarginV,Effect,Text CR LF ) +
* 1 2 3 4 5 6 7 8 9 10
*/
-static hb_buffer_t *ssa_decode_to_utf8( hb_buffer_t *in )
+static hb_buffer_t *ssa_decode_packet( hb_work_object_t * w, hb_buffer_t *in )
{
// Store NULL after the end of the buffer to make using string processing safe
hb_buffer_realloc( in, in->size + 1 );
@@ -119,22 +139,31 @@ static hb_buffer_t *ssa_decode_to_utf8( hb_buffer_t *in )
continue;
// Decode an individual SSA line
- hb_buffer_t *out = ssa_decode_to_utf8_line( (uint8_t*)curLine, strlen( curLine ) );
-
- // We shouldn't be storing the extra NULL character,
- // but the MP4 muxer expects this, unfortunately.
- if ( out->size > 0 && out->data[out->size - 1] != '\0' ) {
- // NOTE: out->size remains unchanged
- hb_buffer_realloc( out, out->size + 1 );
- out->data[out->size] = '\0';
- }
-
- // If the input packet was non-empty, do not pass through
- // an empty output packet (even if the subtitle was empty),
- // as this would be interpreted as an end-of-stream
- if ( in->size > 0 && out->size == 0 ) {
- hb_buffer_close(&out);
- continue;
+ hb_buffer_t *out;
+ if ( w->subtitle->config.dest == PASSTHRUSUB ) {
+ out = ssa_decode_line_to_utf8( (uint8_t *) curLine, strlen( curLine ), in->sequence );
+ if ( out == NULL )
+ continue;
+
+ // We shouldn't be storing the extra NULL character,
+ // but the MP4 muxer expects this, unfortunately.
+ if ( out->size > 0 && out->data[out->size - 1] != '\0' ) {
+ // NOTE: out->size remains unchanged
+ hb_buffer_realloc( out, out->size + 1 );
+ out->data[out->size] = '\0';
+ }
+
+ // If the input packet was non-empty, do not pass through
+ // an empty output packet (even if the subtitle was empty),
+ // as this would be interpreted as an end-of-stream
+ if ( in->size > 0 && out->size == 0 ) {
+ hb_buffer_close(&out);
+ continue;
+ }
+ } else if ( w->subtitle->config.dest == RENDERSUB ) {
+ out = ssa_decode_line_to_picture( w, (uint8_t *) curLine, strlen( curLine ), in->sequence );
+ if ( out == NULL )
+ continue;
}
// Append 'out' to 'out_list'
@@ -146,50 +175,68 @@ static hb_buffer_t *ssa_decode_to_utf8( hb_buffer_t *in )
}
/*
- * SSA line format:
- * Dialogue: Marked,Start,End,Style,Name,MarginL,MarginR,MarginV,Effect,Text '\0'
- * 1 2 3 4 5 6 7 8 9 10
+ * Parses the start and stop time from the specified SSA packet.
+ *
+ * Returns true if parsing failed; false otherwise.
*/
-static hb_buffer_t *ssa_decode_to_utf8_line( uint8_t *in_data, int in_size )
+static int parse_timing_from_ssa_packet( char *in_data, int64_t *in_start, int64_t *in_stop )
{
- uint8_t *pos = in_data;
- uint8_t *end = in_data + in_size;
-
/*
* Parse Start and End fields for timing information
*/
int start_hr, start_min, start_sec, start_centi;
int end_hr, end_min, end_sec, end_centi;
- int numPartsRead = sscanf( (char *) in_data, "%*128[^,],"
+ int numPartsRead = sscanf( (char *) in_data, "Dialogue: %*128[^,],"
"%d:%d:%d.%d," // Start
"%d:%d:%d.%d,", // End
&start_hr, &start_min, &start_sec, &start_centi,
&end_hr, &end_min, &end_sec, &end_centi );
if ( numPartsRead != 8 )
- goto fail;
+ return 1;
- int64_t in_start = SSA_2_HB_TIME(start_hr, start_min, start_sec, start_centi);
- int64_t in_stop = SSA_2_HB_TIME( end_hr, end_min, end_sec, end_centi);
+ *in_start = SSA_2_HB_TIME(start_hr, start_min, start_sec, start_centi);
+ *in_stop = SSA_2_HB_TIME( end_hr, end_min, end_sec, end_centi);
- /*
- * Advance 'pos' to the beginning of the Text field
- */
+ return 0;
+}
+
+static uint8_t *find_field( uint8_t *pos, uint8_t *end, int fieldNum )
+{
int curFieldID = 1;
while (pos < end)
{
if ( *pos++ == ',' )
{
curFieldID++;
- if ( curFieldID == 10 ) // Text
- break;
+ if ( curFieldID == fieldNum )
+ return pos;
}
}
- if ( curFieldID != 10 )
+ return NULL;
+}
+
+/*
+ * SSA line format:
+ * Dialogue: Marked,Start,End,Style,Name,MarginL,MarginR,MarginV,Effect,Text '\0'
+ * 1 2 3 4 5 6 7 8 9 10
+ */
+static hb_buffer_t *ssa_decode_line_to_utf8( uint8_t *in_data, int in_size, int in_sequence )
+{
+ uint8_t *pos = in_data;
+ uint8_t *end = in_data + in_size;
+
+ // Parse values for in->start and in->stop
+ int64_t in_start, in_stop;
+ if ( parse_timing_from_ssa_packet( (char *) in_data, &in_start, &in_stop ) )
+ goto fail;
+
+ uint8_t *textFieldPos = find_field( pos, end, 10 );
+ if ( textFieldPos == NULL )
goto fail;
- uint8_t *textFieldPos = pos;
// Count the number of style overrides in the Text field
int numStyleOverrides = 0;
+ pos = textFieldPos;
while ( pos < end )
{
if (*pos++ == '{')
@@ -207,7 +254,7 @@ static hb_buffer_t *ssa_decode_to_utf8_line( uint8_t *in_data, int in_size )
* The Text field contains plain text marked up with:
* (1) '\n' -> space
* (2) '\N' -> newline
- * (3) curly-brace control codes like '{\k44}' -> empty (strip them)
+ * (3) curly-brace control codes like '{\k44}' -> HTML tags / strip
*
* Perform the above conversions and copy it to the output packet
*/
@@ -253,6 +300,7 @@ static hb_buffer_t *ssa_decode_to_utf8_line( uint8_t *in_data, int in_size )
// Copy metadata from the input packet to the output packet
out->start = in_start;
out->stop = in_stop;
+ out->sequence = in_sequence;
return out;
@@ -261,8 +309,252 @@ fail:
return NULL;
}
+/*
+ * SSA line format:
+ * Dialogue: Marked,Start,End,Style,Name,MarginL,MarginR,MarginV,Effect,Text '\0'
+ * 1 2 3 4 5 6 7 8 9 10
+ *
+ * MKV-SSA packet format:
+ * ReadOrder,Marked, Style,Name,MarginL,MarginR,MarginV,Effect,Text '\0'
+ * 1 2 3 4 5 6 7 8 9
+ */
+static hb_buffer_t *ssa_decode_line_to_picture( hb_work_object_t * w, uint8_t *in_data, int in_size, int in_sequence )
+{
+ hb_work_private_t * pv = w->private_data;
+
+ // Parse values for in->start and in->stop
+ int64_t in_start, in_stop;
+ if ( parse_timing_from_ssa_packet( (char *) in_data, &in_start, &in_stop ) )
+ goto fail;
+
+ // Convert the SSA packet to MKV-SSA format, which is what libass expects
+ char *mkvIn;
+ int mkvInSize;
+ {
+ char *layerField = malloc( in_size );
+ int numPartsRead = sscanf( (char *) in_data, "Dialogue: %128[^,],", layerField );
+ if ( numPartsRead != 1 )
+ goto fail;
+
+ char *styleToTextFields = (char *) find_field( in_data, in_data + in_size, 4 );
+ if ( styleToTextFields == NULL ) {
+ free( layerField );
+ goto fail;
+ }
+
+ mkvIn = malloc( in_size + 1 );
+ mkvIn[0] = '\0';
+ sprintf(mkvIn, "%d", pv->readOrder++); // ReadOrder: make this up
+ strcat( mkvIn, "," );
+ strcat( mkvIn, layerField );
+ strcat( mkvIn, "," );
+ strcat( mkvIn, (char *) styleToTextFields );
+
+ mkvInSize = strlen(mkvIn);
+
+ free( layerField );
+ }
+
+ // Parse MKV-SSA packet
+ ass_process_chunk( pv->ssaTrack, mkvIn, mkvInSize, in_start / 90, (in_stop - in_start) / 90 );
+
+ free( mkvIn );
+
+ // TODO: To support things like karaoke, it won't be sufficient to only generate
+ // new subtitle pictures when there are subtitle packets. Rather, pictures will
+ // need to be generated potentially continuously.
+ //
+ // Until "karaoke support" is implemented, make an educated guess about the
+ // timepoint within the subtitle that should be rendered. I guess the midpoint.
+ int64_t renderTime = ( in_start + in_stop ) / 2;
+
+ int changed;
+ ASS_Image *frameList = ass_render_frame( pv->renderer, pv->ssaTrack, renderTime / 90, &changed );
+ if ( !changed && !frameList )
+ return NULL;
+
+ int numFrames = 0;
+ ASS_Image *curFrame;
+ for (curFrame = frameList; curFrame; curFrame = curFrame->next)
+ numFrames++;
+
+ hb_buffer_t *outSubpictureList = NULL;
+ hb_buffer_t **outSubpictureListTailPtr = &outSubpictureList;
+
+ // Generate a PICTURESUB packet from the frames
+ ASS_Image *frame;
+ for (frame = frameList; frame; frame = frame->next) {
+ // Allocate pixmap where drawing will be done
+ uint8_t *rgba = calloc(frame->w * frame->h * 4, 1);
+
+ unsigned r = (frame->color >> 24) & 0xff;
+ unsigned g = (frame->color >> 16) & 0xff;
+ unsigned b = (frame->color >> 8) & 0xff;
+ unsigned a = (frame->color ) & 0xff;
+
+ int x, y;
+ for (y = 0; y < frame->h; y++) {
+ for (x = 0; x < frame->w; x++) {
+ unsigned srcAlphaPrenormalized = frame->bitmap[y*frame->stride + x];
+ unsigned srcAlpha = (255 - a) * srcAlphaPrenormalized / 255;
+
+ uint8_t *dst = &rgba[(y*frame->w + x) * 4];
+ unsigned oldDstAlpha = dst[3];
+
+ if (oldDstAlpha == 0) {
+ // Optimized version
+ dst[0] = r;
+ dst[1] = g;
+ dst[2] = b;
+ dst[3] = srcAlpha;
+ } else {
+ dst[3] = 255 - ( 255 - dst[3] ) * ( 255 - srcAlpha ) / 255;
+ if (dst[3] != 0) {
+ dst[0] = ( dst[0] * oldDstAlpha * (255-srcAlpha) / 255 + r * srcAlpha ) / dst[3];
+ dst[1] = ( dst[1] * oldDstAlpha * (255-srcAlpha) / 255 + g * srcAlpha ) / dst[3];
+ dst[2] = ( dst[2] * oldDstAlpha * (255-srcAlpha) / 255 + b * srcAlpha ) / dst[3];
+ }
+ }
+ }
+ }
+
+ // Generate output subpicture (in PICTURESUB format)
+ hb_buffer_t *out = hb_buffer_init(frame->w * frame->h * 4);
+ out->x = frame->dst_x;
+ out->y = frame->dst_y;
+ out->width = frame->w;
+ out->height = frame->h;
+
+ int i;
+ int numPixels = frame->w * frame->h;
+ for (i = 0; i < numPixels; i++) {
+ uint8_t *srcRgba = &rgba[i * 4];
+
+ uint8_t *dstY = &out->data[(numPixels * 0) + i];
+ uint8_t *dstA = &out->data[(numPixels * 1) + i];
+ uint8_t *dstU = &out->data[(numPixels * 2) + i];
+ uint8_t *dstV = &out->data[(numPixels * 3) + i];
+
+ int srcYuv = hb_rgb2yuv((srcRgba[0] << 16) | (srcRgba[1] << 8) | (srcRgba[2] << 0));
+ int srcA = srcRgba[3];
+
+ *dstY = (srcYuv >> 16) & 0xff;
+ *dstU = (srcYuv >> 8 ) & 0xff;
+ *dstV = (srcYuv >> 0 ) & 0xff;
+ *dstA = srcA / 16; // HB's max alpha value is 16
+ }
+
+ free(rgba);
+
+ *outSubpictureListTailPtr = out;
+ outSubpictureListTailPtr = &out->next_subpicture;
+ }
+
+ // NOTE: The subpicture list is actually considered a single packet by most other code
+ hb_buffer_t *out = outSubpictureList;
+
+ // Copy metadata from the input packet to the output packet
+ out->start = in_start;
+ out->stop = in_stop;
+ out->sequence = in_sequence;
+
+ return out;
+
+fail:
+ hb_log( "decssasub: malformed SSA subtitle packet: %.*s\n", in_size, in_data );
+ return NULL;
+}
+
+static void ssa_log(int level, const char *fmt, va_list args, void *data)
+{
+ if ( level < 5 ) // same as default verbosity when no callback is set
+ {
+ char *msg;
+ if ( vasprintf( &msg, fmt, args ) < 0 )
+ {
+ hb_log( "decssasub: could not report libass message\n" );
+ return;
+ }
+ hb_log( "[ass] %s", msg ); // no need for extra '\n' because libass sends it
+
+ free( msg );
+ }
+}
+
static int decssaInit( hb_work_object_t * w, hb_job_t * job )
{
+ hb_work_private_t * pv;
+
+ pv = calloc( 1, sizeof( hb_work_private_t ) );
+ w->private_data = pv;
+
+ if ( w->subtitle->config.dest == RENDERSUB ) {
+ pv->ssa = ass_library_init();
+ if ( !pv->ssa ) {
+ hb_log( "decssasub: libass initialization failed\n" );
+ return 1;
+ }
+
+ // Redirect libass output to hb_log
+ ass_set_message_cb( pv->ssa, ssa_log, NULL );
+
+ // Load embedded fonts
+ hb_list_t * list_attachment = job->title->list_attachment;
+ int i;
+ for ( i = 0; i < hb_list_count(list_attachment); i++ )
+ {
+ hb_attachment_t * attachment = hb_list_item( list_attachment, i );
+
+ if ( attachment->type == FONT_TTF_ATTACH )
+ {
+ ass_add_font(
+ pv->ssa,
+ attachment->name,
+ attachment->data,
+ attachment->size );
+ }
+ }
+
+ ass_set_extract_fonts( pv->ssa, 1 );
+ ass_set_style_overrides( pv->ssa, NULL );
+
+ pv->renderer = ass_renderer_init( pv->ssa );
+ if ( !pv->renderer ) {
+ hb_log( "decssasub: renderer initialization failed\n" );
+ return 1;
+ }
+
+ ass_set_use_margins( pv->renderer, 0 );
+ ass_set_hinting( pv->renderer, ASS_HINTING_LIGHT ); // VLC 1.0.4 uses this
+ ass_set_font_scale( pv->renderer, 1.0 );
+ ass_set_line_spacing( pv->renderer, 1.0 );
+
+ // Setup default font family
+ //
+ // SSA v4.00 requires that "Arial" be the default font
+ const char *font = NULL;
+ const char *family = "Arial";
+ // NOTE: This can sometimes block for several *seconds*.
+ // It seems that process_fontdata() for some embedded fonts is slow.
+ ass_set_fonts( pv->renderer, font, family, /*haveFontConfig=*/1, NULL, 1 );
+
+ // Setup track state
+ pv->ssaTrack = ass_new_track( pv->ssa );
+ if ( !pv->ssaTrack ) {
+ hb_log( "decssasub: ssa track initialization failed\n" );
+ return 1;
+ }
+
+ // NOTE: The codec extradata is expected to be in MKV format
+ ass_process_codec_private( pv->ssaTrack,
+ (char *) w->subtitle->extradata, w->subtitle->extradata_size );
+
+ int originalWidth = job->title->width;
+ int originalHeight = job->title->height;
+ ass_set_frame_size( pv->renderer, originalWidth, originalHeight);
+ ass_set_aspect_ratio( pv->renderer, /*dar=*/1.0, /*sar=*/1.0 );
+ }
+
return 0;
}
@@ -273,7 +565,7 @@ static int decssaWork( hb_work_object_t * w, hb_buffer_t ** buf_in,
hb_buffer_t * out_list = NULL;
if ( in->size > 0 ) {
- out_list = ssa_decode_to_utf8(in);
+ out_list = ssa_decode_packet(w, in);
} else {
out_list = hb_buffer_init( 0 );
}
@@ -288,7 +580,16 @@ static int decssaWork( hb_work_object_t * w, hb_buffer_t ** buf_in,
static void decssaClose( hb_work_object_t * w )
{
- // nothing
+ hb_work_private_t * pv = w->private_data;
+
+ if ( pv->ssaTrack )
+ ass_free_track( pv->ssaTrack );
+ if ( pv->renderer )
+ ass_renderer_done( pv->renderer );
+ if ( pv->ssa )
+ ass_library_done( pv->ssa );
+
+ free( w->private_data );
}
hb_work_object_t hb_decssasub =
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 03:07:42 +0000