Andreas Rheinhardt:
> Andreas Rheinhardt:
>> Andreas Rheinhardt:
>>> 1. Since bd90a2ec, mpeg4_unpack_bframes caches whole packets instead of
>>> just the pointer to the buffer and the buffer's size in order to be able
>>> to make use of refcounting to avoid copying of data; this unfortunately
>>> introduced copies of packet structures and side data (if existing),
>>> although the only fields that are needed are the buffer-related ones
>>> (data, size and buf). This can be changed without compromising the
>>> advantages of refcounting by storing a reference to the buffer.
>>>
>>> 2. This change also makes it easy to use only one packet throughout
>>> so that an allocation and free of an AVPacket structure per filtered
>>> packet can be saved by switching to ff_bsf_get_packet_ref.
>>>
>>> 3. Furthermore, this commit also fixes a memleak introduced in bd90a2ec:
>>> If a stored b_frame with side data was used for a later frame, the side
>>> data would leak when the input frame's properties were copied into the
>>> output frame.
>>>
>>> Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com>
>>> ---
>>> libavcodec/mpeg4_unpack_bframes_bsf.c | 77 ++++++++++++---------------
>>> 1 file changed, 35 insertions(+), 42 deletions(-)
>>>
>>> diff --git a/libavcodec/mpeg4_unpack_bframes_bsf.c
>>> b/libavcodec/mpeg4_unpack_bframes_bsf.c
>>> index 1daf133ce5..382070b423 100644
>>> --- a/libavcodec/mpeg4_unpack_bframes_bsf.c
>>> +++ b/libavcodec/mpeg4_unpack_bframes_bsf.c
>>> @@ -25,7 +25,7 @@
>>> #include "mpeg4video.h"
>>>
>>> typedef struct UnpackBFramesBSFContext {
>>> - AVPacket *b_frame;
>>> + AVBufferRef *b_frame_ref;
>>> } UnpackBFramesBSFContext;
>>>
>>> /* determine the position of the packed marker in the userdata,
>>> @@ -56,32 +56,32 @@ static void scan_buffer(const uint8_t *buf, int
>>> buf_size,
>>> }
>>> }
>>>
>>> -static int mpeg4_unpack_bframes_filter(AVBSFContext *ctx, AVPacket *out)
>>> +static int mpeg4_unpack_bframes_filter(AVBSFContext *ctx, AVPacket *pkt)
>>> {
>>> UnpackBFramesBSFContext *s = ctx->priv_data;
>>> int pos_p = -1, nb_vop = 0, pos_vop2 = -1, ret = 0;
>>> - AVPacket *in;
>>>
>>> - ret = ff_bsf_get_packet(ctx, &in);
>>> + ret = ff_bsf_get_packet_ref(ctx, pkt);
>>> if (ret < 0)
>>> return ret;
>>>
>>> - scan_buffer(in->data, in->size, &pos_p, &nb_vop, &pos_vop2);
>>> + scan_buffer(pkt->data, pkt->size, &pos_p, &nb_vop, &pos_vop2);
>>> av_log(ctx, AV_LOG_DEBUG, "Found %d VOP startcode(s) in this
>>> packet.\n", nb_vop);
>>>
>>> if (pos_vop2 >= 0) {
>>> - if (s->b_frame->data) {
>>> + if (s->b_frame_ref) {
>>> av_log(ctx, AV_LOG_WARNING,
>>> "Missing one N-VOP packet, discarding one B-frame.\n");
>>> - av_packet_unref(s->b_frame);
>>> + av_buffer_unref(&s->b_frame_ref);
>>> }
>>> - /* store the packed B-frame in the BSFContext */
>>> - ret = av_packet_ref(s->b_frame, in);
>>> - if (ret < 0) {
>>> + /* store a reference to the packed B-frame's data in the
>>> BSFContext */
>>> + s->b_frame_ref = av_buffer_ref(pkt->buf);
>>> + if (!s->b_frame_ref) {
>>> + ret = AVERROR(ENOMEM);
>>> goto fail;
>>> }
>>> - s->b_frame->size -= pos_vop2;
>>> - s->b_frame->data += pos_vop2;
>>> + s->b_frame_ref->data = pkt->data + pos_vop2;
>>> + s->b_frame_ref->size = pkt->size - pos_vop2;
>>> }
>>>
>>> if (nb_vop > 2) {
>>> @@ -89,56 +89,49 @@ static int mpeg4_unpack_bframes_filter(AVBSFContext
>>> *ctx, AVPacket *out)
>>> "Found %d VOP headers in one packet, only unpacking one.\n",
>>> nb_vop);
>>> }
>>>
>>> - if (nb_vop == 1 && s->b_frame->data) {
>>> - /* use frame from BSFContext */
>>> - av_packet_move_ref(out, s->b_frame);
>>> + if (nb_vop == 1 && s->b_frame_ref) {
>>> + AVBufferRef *tmp = pkt->buf;
>>>
>>> - /* use properties from current input packet */
>>> - ret = av_packet_copy_props(out, in);
>>> - if (ret < 0) {
>>> - goto fail;
>>> - }
>>> + /* make tmp accurately reflect the packet's data */
>>> + tmp->data = pkt->data;
>>> + tmp->size = pkt->size;
>>> +
>>> + /* replace data in packet with stored data */
>>> + pkt->buf = s->b_frame_ref;
>>> + pkt->data = s->b_frame_ref->data;
>>> + pkt->size = s->b_frame_ref->size;
>>> +
>>> + /* store reference to data into BSFContext */
>>> + s->b_frame_ref = tmp;
>>>
>>> - if (in->size <= MAX_NVOP_SIZE) {
>>> - /* N-VOP */
>>> + if (s->b_frame_ref->size <= MAX_NVOP_SIZE) {
>>> + /* N-VOP - discard stored data */
>>> av_log(ctx, AV_LOG_DEBUG, "Skipping N-VOP.\n");
>>> - } else {
>>> - /* copy packet into BSFContext */
>>> - av_packet_move_ref(s->b_frame, in);
>>> + av_buffer_unref(&s->b_frame_ref);
>>> }
>>> } else if (nb_vop >= 2) {
>>> /* use first frame of the packet */
>>> - av_packet_move_ref(out, in);
>>> - out->size = pos_vop2;
>>> + pkt->size = pos_vop2;
>>> } else if (pos_p >= 0) {
>>> - ret = av_packet_make_writable(in);
>>> + ret = av_packet_make_writable(pkt);
>>> if (ret < 0)
>>> goto fail;
>>> av_log(ctx, AV_LOG_DEBUG, "Updating DivX userdata (remove trailing
>>> 'p').\n");
>>> - av_packet_move_ref(out, in);
>>> /* remove 'p' (packed) from the end of the (DivX) userdata string
>>> */
>>> - out->data[pos_p] = '\0';
>>> + pkt->data[pos_p] = '\0';
>>> } else {
>>> - /* copy packet */
>>> - av_packet_move_ref(out, in);
>>> + /* use packet as is */
>>> }
>>>
>>> fail:
>>> if (ret < 0)
>>> - av_packet_unref(out);
>>> - av_packet_free(&in);
>>> + av_packet_unref(pkt);
>>>
>>> return ret;
>>> }
>>>
>>> static int mpeg4_unpack_bframes_init(AVBSFContext *ctx)
>>> {
>>> - UnpackBFramesBSFContext *s = ctx->priv_data;
>>> -
>>> - s->b_frame = av_packet_alloc();
>>> - if (!s->b_frame)
>>> - return AVERROR(ENOMEM);
>>> -
>>> if (ctx->par_in->extradata) {
>>> int pos_p_ext = -1;
>>> scan_buffer(ctx->par_in->extradata, ctx->par_in->extradata_size,
>>> &pos_p_ext, NULL, NULL);
>>> @@ -155,13 +148,13 @@ static int mpeg4_unpack_bframes_init(AVBSFContext
>>> *ctx)
>>> static void mpeg4_unpack_bframes_flush(AVBSFContext *bsfc)
>>> {
>>> UnpackBFramesBSFContext *ctx = bsfc->priv_data;
>>> - av_packet_unref(ctx->b_frame);
>>> + av_buffer_unref(&ctx->b_frame_ref);
>>> }
>>>
>>> static void mpeg4_unpack_bframes_close(AVBSFContext *bsfc)
>>> {
>>> UnpackBFramesBSFContext *ctx = bsfc->priv_data;
>>> - av_packet_free(&ctx->b_frame);
>>> + av_buffer_unref(&ctx->b_frame_ref);
>>> }
>>>
>>> static const enum AVCodecID codec_ids[] = {
>>>
>> Ping.
>>
>> - Andreas
>>
> Another ping.
>
> - Andreas
>
And another ping.
- Andreas
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
