From: Niklesh <niklesh.lalw...@iitb.ac.in>
This patch adds support for decoding of Highlight and hilightcolor box as
defined by 3GPP standards.
The code is also reorganised to make it easier to maintain and read. Separate
functions are defined that process each type of box.
Signed-off-by: Niklesh <niklesh.lalw...@iitb.ac.in>
---
libavcodec/movtextdec.c | 253 ++++++++++++++++++++++++++++++++----------------
1 file changed, 172 insertions(+), 81 deletions(-)
diff --git a/libavcodec/movtextdec.c b/libavcodec/movtextdec.c
index a3afd91..0dab0b4 100644
--- a/libavcodec/movtextdec.c
+++ b/libavcodec/movtextdec.c
@@ -37,31 +37,157 @@ typedef struct {
uint8_t style_flag;
} StyleBox;
+typedef struct {
+ uint16_t hlit_start;
+ uint16_t hlit_end;
+} HighlightBox;
+
+typedef struct {
+ uint8_t hlit_color[4];
+} HilightcolorBox;
+
+typedef struct {
+ int styl;
+ int hlit;
+ int hclr;
+} Box_flags;
+
+typedef struct {
+ StyleBox **s;
+ StyleBox *s_temp;
+ HighlightBox h;
+ HilightcolorBox c;
+ Box_flags f;
+ uint16_t style_entries;
+ uint64_t tracksize;
+ int size_var;
+ int count_s;
+} MovTextContext;
+
+struct Box
+{
+ uint32_t type;
+ size_t base_size;
+ int (*decode)(const uint8_t *tsmb, MovTextContext *m, AVPacket *avpkt);
+};
+
+static void mov_text_cleanup(MovTextContext *m)
+{
+ int i;
+ if (m->f.styl) {
+ for(i = 0; i < m->count_s; i++) {
+ av_freep(&m->s[i]);
+ }
+ av_freep(&m->s);
+ }
+}
+
+static int decode_hlit(const uint8_t *tsmb, MovTextContext *m, AVPacket *avpkt)
+{
+ m->f.hlit = 1;
+ m->h.hlit_start = AV_RB16(tsmb);
+ tsmb += 2;
+ m->h.hlit_end = AV_RB16(tsmb);
+ tsmb += 2;
+ return 0;
+}
+
+static int decode_hclr(const uint8_t *tsmb, MovTextContext *m, AVPacket *avpkt)
+{
+ m->f.hclr = 1;
+ m->c.hlit_color[0] = *tsmb++;
+ m->c.hlit_color[1] = *tsmb++;
+ m->c.hlit_color[2] = *tsmb++;
+ m->c.hlit_color[3] = *tsmb++;
+ return 0;
+}
+
+static int decode_styl(const uint8_t *tsmb, MovTextContext *m, AVPacket *avpkt)
+{
+ int i;
+ m->style_entries = AV_RB16(tsmb);
+ tsmb += 2;
+ // A single style record is of length 12 bytes.
+ if (m->tracksize + m->size_var + 2 + m->style_entries * 12 > avpkt->size)
+ return -1;
+
+ m->f.styl = 1;
+ for(i = 0; i < m->style_entries; i++) {
+ m->s_temp = av_malloc(sizeof(StyleBox));
+ if (!m->s_temp) {
+ mov_text_cleanup(m);
+ return AVERROR(ENOMEM);
+ }
+ m->s_temp->style_start = AV_RB16(tsmb);
+ tsmb += 2;
+ m->s_temp->style_end = AV_RB16(tsmb);
+ tsmb += 2;
+ // fontID = AV_RB16(tsmb);
+ tsmb += 2;
+ m->s_temp->style_flag = AV_RB8(tsmb);
+ av_dynarray_add(&m->s, &m->count_s, m->s_temp);
+ if(!m->s) {
+ mov_text_cleanup(m);
+ return AVERROR(ENOMEM);
+ }
+ // fontsize = AV_RB8(tsmb);
+ tsmb += 2;
+ // text-color-rgba
+ tsmb += 4;
+ }
+ return 0;
+}
+
+struct Box box_types[] = {
+ { MKBETAG('s','t','y','l'), 2, decode_styl },
+ { MKBETAG('h','l','i','t'), 4, decode_hlit },
+ { MKBETAG('h','c','l','r'), 4, decode_hclr }
+};
+
+const static size_t box_count = sizeof(box_types) / sizeof(struct Box);
+
static int text_to_ass(AVBPrint *buf, const char *text, const char *text_end,
- StyleBox **s, int style_entries)
+ MovTextContext *m)
{
int i = 0;
int text_pos = 0;
while (text < text_end) {
- for (i = 0; i < style_entries; i++) {
- if (s[i]->style_flag && text_pos == s[i]->style_end) {
- if (s[i]->style_flag & STYLE_FLAG_BOLD)
- av_bprintf(buf, "{\\b0}");
- if (s[i]->style_flag & STYLE_FLAG_ITALIC)
- av_bprintf(buf, "{\\i0}");
- if (s[i]->style_flag & STYLE_FLAG_UNDERLINE)
- av_bprintf(buf, "{\\u0}");
+ if (m->f.styl) {
+ for (i = 0; i < m->style_entries; i++) {
+ if (m->s[i]->style_flag && text_pos == m->s[i]->style_end) {
+ if (m->s[i]->style_flag & STYLE_FLAG_BOLD)
+ av_bprintf(buf, "{\\b0}");
+ if (m->s[i]->style_flag & STYLE_FLAG_ITALIC)
+ av_bprintf(buf, "{\\i0}");
+ if (m->s[i]->style_flag & STYLE_FLAG_UNDERLINE)
+ av_bprintf(buf, "{\\u0}");
+ }
+ }
+ for (i = 0; i < m->style_entries; i++) {
+ if (m->s[i]->style_flag && text_pos == m->s[i]->style_start) {
+ if (m->s[i]->style_flag & STYLE_FLAG_BOLD)
+ av_bprintf(buf, "{\\b1}");
+ if (m->s[i]->style_flag & STYLE_FLAG_ITALIC)
+ av_bprintf(buf, "{\\i1}");
+ if (m->s[i]->style_flag & STYLE_FLAG_UNDERLINE)
+ av_bprintf(buf, "{\\u1}");
+ }
}
}
-
- for (i = 0; i < style_entries; i++) {
- if (s[i]->style_flag && text_pos == s[i]->style_start) {
- if (s[i]->style_flag & STYLE_FLAG_BOLD)
- av_bprintf(buf, "{\\b1}");
- if (s[i]->style_flag & STYLE_FLAG_ITALIC)
- av_bprintf(buf, "{\\i1}");
- if (s[i]->style_flag & STYLE_FLAG_UNDERLINE)
- av_bprintf(buf, "{\\u1}");
+ if (m->f.hlit) {
+ if (text_pos == m->h.hlit_start) {
+ if (m->f.hclr) {
+ av_bprintf(buf, "{\\2c&H%02x%02x%02x&}",
m->c.hlit_color[2], m->c.hlit_color[1], m->c.hlit_color[0]);
+ } else {
+ av_bprintf(buf, "{\\1c&H000000&}{\\2c&HFFFFFF}");
+ }
+ }
+ if (text_pos == m->h.hlit_end) {
+ if (m->f.hclr) {
+ av_bprintf(buf, "{\\2c&H000000}");
+ } else {
+ av_bprintf(buf, "{\\1c&HFFFFFF&}{\\2c&H000000}");
+ }
}
}
@@ -78,7 +204,6 @@ static int text_to_ass(AVBPrint *buf, const char *text,
const char *text_end,
text++;
text_pos++;
}
-
return 0;
}
@@ -96,17 +221,14 @@ static int mov_text_decode_frame(AVCodecContext *avctx,
void *data, int *got_sub_ptr, AVPacket *avpkt)
{
AVSubtitle *sub = data;
+ MovTextContext *m = avctx->priv_data;
int ret, ts_start, ts_end;
AVBPrint buf;
char *ptr = avpkt->data;
char *end;
- //char *ptr_temp;
- int text_length, tsmb_type, style_entries;
- uint64_t tsmb_size, tracksize;
- StyleBox **s = {0, };
- StyleBox *s_temp;
+ int text_length, tsmb_type, ret_tsmb;
+ uint64_t tsmb_size;
const uint8_t *tsmb;
- int count, i, size_var;
if (!ptr || avpkt->size < 2)
return AVERROR_INVALIDDATA;
@@ -138,73 +260,51 @@ static int mov_text_decode_frame(AVCodecContext *avctx,
(AVRational){1,100});
tsmb_size = 0;
- tracksize = 2 + text_length;
+ m->tracksize = 2 + text_length;
+ m->style_entries = 0;
+ m->f.styl = 0;
+ m->f.hlit = 0;
+ m->f.hclr = 0;
+ m->count_s = 0;
// Note that the spec recommends lines be no longer than 2048 characters.
av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
if (text_length + 2 != avpkt->size) {
- while (tracksize + 8 <= avpkt->size) {
+ while (m->tracksize + 8 <= avpkt->size) {
// A box is a minimum of 8 bytes.
- tsmb = ptr + tracksize - 2;
+ tsmb = ptr + m->tracksize - 2;
tsmb_size = AV_RB32(tsmb);
tsmb += 4;
tsmb_type = AV_RB32(tsmb);
tsmb += 4;
if (tsmb_size == 1) {
- if (tracksize + 16 > avpkt->size)
+ if (m->tracksize + 16 > avpkt->size)
break;
tsmb_size = AV_RB64(tsmb);
tsmb += 8;
- size_var = 18;
+ m->size_var = 16;
} else
- size_var = 10;
- //size_var is equal to 10 or 18 depending on the size of box
+ m->size_var = 8;
+ //size_var is equal to 8 or 16 depending on the size of box
- if (tracksize + tsmb_size > avpkt->size)
+ if (m->tracksize + tsmb_size > avpkt->size)
break;
- if (tsmb_type == MKBETAG('s','t','y','l')) {
- if (tracksize + size_var > avpkt->size)
- break;
- style_entries = AV_RB16(tsmb);
- tsmb += 2;
-
- // A single style record is of length 12 bytes.
- if (tracksize + size_var + style_entries * 12 > avpkt->size)
- break;
- count = 0;
-
- for(i = 0; i < style_entries; i++) {
- s_temp = av_malloc(sizeof(*s_temp));
- if (!s_temp)
- goto error;
-
- s_temp->style_start = AV_RB16(tsmb);
- tsmb += 2;
- s_temp->style_end = AV_RB16(tsmb);
- tsmb += 2;
- // fontID = AV_RB16(tsmb);
- tsmb += 2;
- s_temp->style_flag = AV_RB8(tsmb);
- av_dynarray_add(&s, &count, s_temp);
- if(!s)
- goto error;
- //fontsize=AV_RB8(tsmb);
- tsmb += 2;
- // text-color-rgba
- tsmb += 4;
- }
- text_to_ass(&buf, ptr, end, s, style_entries);
-
- for(i = 0; i < count; i++) {
- av_freep(&s[i]);
+ for (size_t i = 0; i < box_count; i++) {
+ if (tsmb_type == box_types[i].type) {
+ if (m->tracksize + m->size_var + box_types[i].base_size >
avpkt->size)
+ break;
+ ret_tsmb = box_types[i].decode(tsmb, m, avpkt);
+ if (ret_tsmb == -1)
+ break;
}
- av_freep(&s);
}
- tracksize = tracksize + tsmb_size;
+ m->tracksize = m->tracksize + tsmb_size;
}
+ text_to_ass(&buf, ptr, end, m);
+ mov_text_cleanup(m);
} else
- text_to_ass(&buf, ptr, end, NULL, 0);
+ text_to_ass(&buf, ptr, end, m);
ret = ff_ass_add_rect_bprint(sub, &buf, ts_start, ts_end - ts_start);
av_bprint_finalize(&buf, NULL);
@@ -212,16 +312,6 @@ static int mov_text_decode_frame(AVCodecContext *avctx,
return ret;
*got_sub_ptr = sub->num_rects > 0;
return avpkt->size;
-
-error:
- for(i = 0; i < count; i++) {
- av_freep(&s[i]);
- }
- av_freep(&s);
- if (s_temp)
- av_freep(&s_temp);
- av_bprint_finalize(&buf, NULL);
- return AVERROR(ENOMEM);
}
AVCodec ff_movtext_decoder = {
@@ -229,6 +319,7 @@ AVCodec ff_movtext_decoder = {
.long_name = NULL_IF_CONFIG_SMALL("3GPP Timed Text subtitle"),
.type = AVMEDIA_TYPE_SUBTITLE,
.id = AV_CODEC_ID_MOV_TEXT,
+ .priv_data_size = sizeof(MovTextContext),
.init = mov_text_init,
.decode = mov_text_decode_frame,
};
--
1.9.1
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