On Sun, Jun 21, 2020 at 09:30:12PM +0800, lance.lmw...@gmail.com wrote:
> From: Limin Wang <lance.lmw...@gmail.com>
>
> Signed-off-by: Limin Wang <lance.lmw...@gmail.com>
> ---
> It's old patch, rebase with master, now have tested with the mpeg2 sample
> for ticket 6105, the output srt is same.
>
> libavcodec/mpeg12dec.c | 85
> ++++++++++++++++++++++++--------------------------
> 1 file changed, 40 insertions(+), 45 deletions(-)
>
> diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c
> index 1253bde..f0f92ac 100644
> --- a/libavcodec/mpeg12dec.c
> +++ b/libavcodec/mpeg12dec.c
> @@ -57,8 +57,7 @@ typedef struct Mpeg1Context {
> AVPanScan pan_scan; /* some temporary storage for the panscan */
> AVStereo3D stereo3d;
> int has_stereo3d;
> - uint8_t *a53_caption;
> - int a53_caption_size;
> + AVBufferRef *a53_buf_ref;
> uint8_t afd;
> int has_afd;
> int slice_count;
> @@ -1635,13 +1634,13 @@ 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->a53_caption) {
> - AVFrameSideData *sd = av_frame_new_side_data(
> + if (s1->a53_buf_ref) {
> + AVFrameSideData *sd = av_frame_new_side_data_from_buf(
> s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
> - s1->a53_caption_size);
> - if (sd)
> - memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
> - av_freep(&s1->a53_caption);
> + s1->a53_buf_ref);
> + if (!sd)
> + av_buffer_unref(&s1->a53_buf_ref);
> + s1->a53_buf_ref = NULL;
> }
>
> if (s1->has_stereo3d) {
> @@ -2242,26 +2241,18 @@ static int mpeg_decode_a53_cc(AVCodecContext *avctx,
> /* extract A53 Part 4 CC data */
> int cc_count = p[5] & 0x1f;
> if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
> - if (s1->a53_caption && s1->a53_caption_size > 0) {
> - uint8_t *old_a53_caption = s1->a53_caption;
> - int old_a53_caption_size = s1->a53_caption_size;
> -
> - s1->a53_caption_size = old_a53_caption_size + cc_count * 3;
> - s1->a53_caption = av_malloc(s1->a53_caption_size);
> - if (s1->a53_caption) {
> - memcpy(s1->a53_caption, old_a53_caption,
> old_a53_caption_size);
> - memcpy(s1->a53_caption + old_a53_caption_size, p + 7,
> cc_count * 3);
> - }
> - av_freep(&old_a53_caption);
> - } else {
> - s1->a53_caption_size = cc_count * 3;
> - s1->a53_caption = av_malloc(s1->a53_caption_size);
> - if (s1->a53_caption)
> - memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
> - }
> - if (!s1->a53_caption) {
> - s1->a53_caption_size = 0;
> - }
> + int old_size = s1->a53_buf_ref ? s1->a53_buf_ref->size : 0;
> + const uint64_t new_size = (old_size + cc_count
> + * UINT64_C(3));
> + int ret;
> +
> + if (new_size > INT_MAX)
> + return AVERROR(EINVAL);
> +
> + ret = av_buffer_realloc(&s1->a53_buf_ref, new_size);
> + if (ret >= 0)
> + memcpy(s1->a53_buf_ref->data + old_size, p + 7, cc_count *
> UINT64_C(3));
> +
> avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
> }
> return 1;
> @@ -2270,19 +2261,21 @@ static int mpeg_decode_a53_cc(AVCodecContext *avctx,
> /* extract SCTE-20 CC data */
> GetBitContext gb;
> int cc_count = 0;
> - int i;
> + int i, ret;
>
> init_get_bits(&gb, p + 2, buf_size - 2);
> cc_count = get_bits(&gb, 5);
> if (cc_count > 0) {
> - av_freep(&s1->a53_caption);
> - s1->a53_caption_size = cc_count * 3;
> - s1->a53_caption = av_mallocz(s1->a53_caption_size);
> - if (!s1->a53_caption) {
> - s1->a53_caption_size = 0;
> - } else {
> + int old_size = s1->a53_buf_ref ? s1->a53_buf_ref->size : 0;
> + const uint64_t new_size = (old_size + cc_count
> + * UINT64_C(3));
> + if (new_size > INT_MAX)
> + return AVERROR(EINVAL);
> +
> + ret = av_buffer_realloc(&s1->a53_buf_ref, new_size);
> + if (ret >= 0) {
> uint8_t field, cc1, cc2;
> - uint8_t *cap = s1->a53_caption;
> + uint8_t *cap = s1->a53_buf_ref->data;
> for (i = 0; i < cc_count && get_bits_left(&gb) >= 26; i++) {
> skip_bits(&gb, 2); // priority
> field = get_bits(&gb, 2);
> @@ -2334,21 +2327,23 @@ static int mpeg_decode_a53_cc(AVCodecContext *avctx,
> * on the even field. There also exist DVDs in the wild that encode
> an odd field count and the
> * caption_extra_field_added/caption_odd_field_first bits change per
> packet to allow that. */
> int cc_count = 0;
> - int i;
> + int i, ret;
> // There is a caption count field in the data, but it is often
> // incorrect. So count the number of captions present.
> 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) {
> - av_freep(&s1->a53_caption);
> - s1->a53_caption_size = cc_count * 6;
> - s1->a53_caption = av_malloc(s1->a53_caption_size);
> - if (!s1->a53_caption) {
> - s1->a53_caption_size = 0;
> - } else {
> + int old_size = s1->a53_buf_ref ? s1->a53_buf_ref->size : 0;
> + const uint64_t new_size = (old_size + cc_count
> + * UINT64_C(6));
> + if (new_size > INT_MAX)
> + return AVERROR(EINVAL);
> +
> + ret = av_buffer_realloc(&s1->a53_buf_ref, new_size);
> + if (ret >= 0) {
> uint8_t field1 = !!(p[4] & 0x80);
> - uint8_t *cap = s1->a53_caption;
> + uint8_t *cap = s1->a53_buf_ref->data;
> p += 5;
> for (i = 0; i < cc_count; i++) {
> cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
> @@ -2886,7 +2881,7 @@ static av_cold int mpeg_decode_end(AVCodecContext
> *avctx)
> Mpeg1Context *s = avctx->priv_data;
>
> ff_mpv_common_end(&s->mpeg_enc_ctx);
> - av_freep(&s->a53_caption);
> + av_buffer_unref(&s->a53_buf_ref);
> return 0;
> }
>
> --
> 1.8.3.1
>
ping, will apply tomorrow if no objection.
--
Thanks,
Limin Wang
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