[FFmpeg-devel] [PATCH] movtextdec: Add support for automatic text wrapping

[Philip Langdale]

On Fri, 14 Aug 2015 20:19:51 +0530
Niklesh Lalwani <niklesh.lalwani at iitb.ac.in> wrote:

> From: Niklesh <niklesh.lalwani at iitb.ac.in>
> 
> The value of wrap_flag in the Text Wrap Box specifies if the text is
> to be wrapped or not. Uses 'end of line wrap' amongst the wrap styles
> supported by ASS if the text is to be wrapped, i.e; fill as much text
> in a line as possible, then break to next line. The 3GPP spec has no
> provision for smart wrapping.
> 
> Signed-off-by: Niklesh <niklesh.lalwani at iitb.ac.in>
> ---
>  libavcodec/movtextdec.c | 25 ++++++++++++++++++++++++-
>  1 file changed, 24 insertions(+), 1 deletion(-)

Pushed. Thanks.

> diff --git a/libavcodec/movtextdec.c b/libavcodec/movtextdec.c
> index 6d7885b..8f1015a 100644
> --- a/libavcodec/movtextdec.c
> +++ b/libavcodec/movtextdec.c
> @@ -36,6 +36,7 @@
>  #define STYL_BOX   (1<<0)
>  #define HLIT_BOX   (1<<1)
>  #define HCLR_BOX   (1<<2)
> +#define TWRP_BOX   (1<<3)
>  
>  #define BOTTOM_LEFT     1
>  #define BOTTOM_CENTER   2
> @@ -81,12 +82,17 @@ typedef struct {
>  } HilightcolorBox;
>  
>  typedef struct {
> +    uint8_t wrap_flag;
> +} TextWrapBox;
> +
> +typedef struct {
>      StyleBox **s;
>      StyleBox *s_temp;
>      HighlightBox h;
>      HilightcolorBox c;
>      FontRecord **ftab;
>      FontRecord *ftab_temp;
> +    TextWrapBox w;
>      MovTextDefault d;
>      uint8_t box_flags;
>      uint16_t style_entries, ftab_entries;
> @@ -240,6 +246,13 @@ static int mov_text_tx3g(AVCodecContext *avctx,
> MovTextContext *m) return 0;
>  }
>  
> +static int decode_twrp(const uint8_t *tsmb, MovTextContext *m,
> AVPacket *avpkt) +{
> +    m->box_flags |= TWRP_BOX;
> +    m->w.wrap_flag = *tsmb++;
> +    return 0;
> +}
> +
>  static int decode_hlit(const uint8_t *tsmb, MovTextContext *m,
> AVPacket *avpkt) {
>      m->box_flags |= HLIT_BOX;
> @@ -298,7 +311,8 @@ static int decode_styl(const uint8_t *tsmb,
> MovTextContext *m, AVPacket *avpkt) static const 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 }
> +    { MKBETAG('h','c','l','r'), 4, decode_hclr },
> +    { MKBETAG('t','w','r','p'), 1, decode_twrp }
>  };
>  
>  const static size_t box_count = FF_ARRAY_ELEMS(box_types);
> @@ -309,6 +323,15 @@ static int text_to_ass(AVBPrint *buf, const char
> *text, const char *text_end, int i = 0;
>      int j = 0;
>      int text_pos = 0;
> +
> +    if (text < text_end && m->box_flags & TWRP_BOX) {
> +        if (m->w.wrap_flag == 1) {
> +            av_bprintf(buf, "{\\q1}"); /* End of line wrap */
> +        } else {
> +            av_bprintf(buf, "{\\q2}"); /* No wrap */
> +        }
> +    }
> +
>      while (text < text_end) {
>          if (m->box_flags & STYL_BOX) {
>              for (i = 0; i < m->style_entries; i++) {




--phil