On 24/11/13 00:11, John Stebbins wrote:
> ---
> libavcodec/avcodec.h | 5 +++++
> libavcodec/mpeg12dec.c | 55
> ++++++++++++++++++++++++++++++++++++++++++++++++++
> libavutil/frame.h | 1 +
> 3 files changed, 61 insertions(+)
>
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index 4ce6d61..9e7d968 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -845,6 +845,11 @@ typedef struct AVPanScan{
> int16_t position[3][2];
> }AVPanScan;
>
> +typedef struct AVClosedCaption {
> + int count;
> + uint8_t data[1];
> +} AVClosedCaption;
> +
> #if FF_API_QSCALE_TYPE
> #define FF_QSCALE_TYPE_MPEG1 0
> #define FF_QSCALE_TYPE_MPEG2 1
> diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c
> index 0e11dda..5543caa 100644
> --- a/libavcodec/mpeg12dec.c
> +++ b/libavcodec/mpeg12dec.c
> @@ -44,6 +44,7 @@ typedef struct Mpeg1Context {
> int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
> int repeat_field; /* true if we must repeat the field */
> AVPanScan pan_scan; /**< some temporary storage for the
> panscan */
> + AVClosedCaption *caption;
> int slice_count;
> int save_aspect_info;
> int save_width, save_height, save_progressive_seq;
> @@ -1529,6 +1530,15 @@ static int mpeg_field_start(MpegEncContext *s, const
> uint8_t *buf, int buf_size)
> return AVERROR(ENOMEM);
> memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
>
> + if (s1->caption != NULL) {
> + int size = sizeof(AVClosedCaption) + s1->caption->count * 3;
> + AVFrameSideData *sd = av_frame_new_side_data(
> + &s->current_picture_ptr->f, AV_FRAME_DATA_CC, size);
> + if (sd != NULL) {
> + memcpy(sd->data, s1->caption, size);
> + }
> + av_freep(&s1->caption);
> + }
> if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
> ff_thread_finish_setup(avctx);
> } else { // second field
> @@ -2041,6 +2051,7 @@ static int vcr2_init_sequence(AVCodecContext *avctx)
> static void mpeg_decode_user_data(AVCodecContext *avctx,
> const uint8_t *p, int buf_size)
> {
> + Mpeg1Context *s1 = avctx->priv_data;
> const uint8_t *buf_end = p + buf_size;
>
> /* we parse the DTG active format information */
> @@ -2058,6 +2069,49 @@ static void mpeg_decode_user_data(AVCodecContext
> *avctx,
> avctx->dtg_active_format = p[0] & 0x0f;
> }
> }
Could you make the following lines a function?
> + /* extract A53 Part 4 CC data */
> + else if (buf_size >= 6 &&
> + p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' && p[4] ==
> 3) {
> + int cc_count = p[5] & 0x1f;
> + if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
> + s1->caption = av_malloc(sizeof(AVClosedCaption) + cc_count * 3);
> + if (s1->caption != NULL) {
> + s1->caption->count = cc_count;
> + memcpy(s1->caption->data, p + 7, cc_count * 3);
> + }
> + }
> + }
> + /* extract DVD CC data */
> + else if (buf_size >= 11 &&
> + p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
> + int cc_count = 0;
> + int i;
> + // There is a caption count field in the data, but it is often
> + // incorect. So count the number of captions present.
^^ <- r
> + for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6) {
> + cc_count++;
> + }
> + // Transform the DVD format into A53 Part 4 format
> + if (cc_count > 0) {
> + s1->caption = av_malloc(sizeof(AVClosedCaption) + cc_count * 6);
> + if (s1->caption != NULL) {
> + uint8_t field1 = !!(p[4] & 0x80);
> + uint8_t *cap = s1->caption->data;
> + p += 5;
> + s1->caption->count = cc_count * 2;
> + for (i = 0; i < cc_count; i++) {
> + cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
> + cap[1] = p[1];
> + cap[2] = p[2];
> + cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
> + cap[4] = p[4];
> + cap[5] = p[5];
> + cap += 6;
> + p += 6;
> + }
> + }
> + }
> + }
> }
>
It doesn't look bad at all.
lu
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