[FFmpeg-devel] [PATCH 1/2] lavc/videotoolboxenc: fix allocated buffer size
Rick Kern
kernrj at gmail.com
Thu Jun 2 08:43:55 CEST 2016
Allocates a buffer with padding, and with enough room for start codes when
length codes are smaller.
Signed-off-by: Rick Kern <kernrj at gmail.com>
---
libavcodec/videotoolboxenc.c | 223 ++++++++++++++++++-------------------------
1 file changed, 94 insertions(+), 129 deletions(-)
diff --git a/libavcodec/videotoolboxenc.c b/libavcodec/videotoolboxenc.c
index 57ea2b3..f4f0d8e 100644
--- a/libavcodec/videotoolboxenc.c
+++ b/libavcodec/videotoolboxenc.c
@@ -199,6 +199,45 @@ static void vtenc_q_push(VTEncContext *vtctx, CMSampleBufferRef buffer)
pthread_mutex_unlock(&vtctx->lock);
}
+static int count_nalus(size_t length_code_size,
+ CMSampleBufferRef sample_buffer,
+ int *count)
+{
+ size_t offset = 0;
+ int status;
+ int nalu_ct = 0;
+ uint8_t size_buf[4];
+ size_t src_size = CMSampleBufferGetTotalSampleSize(sample_buffer);
+ CMBlockBufferRef block = CMSampleBufferGetDataBuffer(sample_buffer);
+
+ if (length_code_size > 4)
+ return AVERROR_INVALIDDATA;
+
+ while (offset < src_size) {
+ size_t curr_src_len;
+ size_t box_len = 0;
+ size_t i;
+
+ status = CMBlockBufferCopyDataBytes(block,
+ offset,
+ length_code_size,
+ size_buf);
+
+ for (i = 0; i < length_code_size; i++) {
+ box_len <<= 8;
+ box_len |= size_buf[i];
+ }
+
+ curr_src_len = box_len + length_code_size;
+ offset += curr_src_len;
+
+ nalu_ct++;
+ }
+
+ *count = nalu_ct;
+ return 0;
+}
+
static CMVideoCodecType get_cm_codec_type(enum AVCodecID id)
{
switch (id) {
@@ -207,12 +246,6 @@ static CMVideoCodecType get_cm_codec_type(enum AVCodecID id)
}
}
-static void vtenc_free_block(void *opaque, uint8_t *data)
-{
- CMBlockBufferRef block = opaque;
- CFRelease(block);
-}
-
/**
* Get the parameter sets from a CMSampleBufferRef.
* @param dst If *dst isn't NULL, the parameters are copied into existing
@@ -1081,54 +1114,6 @@ static void vtenc_get_frame_info(CMSampleBufferRef buffer, bool *is_key_frame)
}
/**
- * Replaces length codes with H.264 Annex B start codes.
- * length_code_size must equal sizeof(start_code).
- * On failure, the contents of data may have been modified.
- *
- * @param length_code_size Byte length of each length code
- * @param data Call with NAL units prefixed with length codes.
- * On success, the length codes are replace with
- * start codes.
- * @param size Length of data, excluding any padding.
- * @return 0 on success
- * AVERROR_BUFFER_TOO_SMALL if length code size is smaller
- * than a start code or if a length_code in data specifies
- * data beyond the end of its buffer.
- */
-static int replace_length_codes(size_t length_code_size,
- uint8_t *data,
- size_t size)
-{
- size_t remaining_size = size;
-
- if (length_code_size != sizeof(start_code)) {
- av_log(NULL, AV_LOG_ERROR, "Start code size and length code size not equal.\n");
- return AVERROR_BUFFER_TOO_SMALL;
- }
-
- while (remaining_size > 0) {
- size_t box_len = 0;
- size_t i;
-
- for (i = 0; i < length_code_size; i++) {
- box_len <<= 8;
- box_len |= data[i];
- }
-
- if (remaining_size < box_len + sizeof(start_code)) {
- av_log(NULL, AV_LOG_ERROR, "Length is out of range.\n");
- AVERROR_BUFFER_TOO_SMALL;
- }
-
- memcpy(data, start_code, sizeof(start_code));
- data += box_len + sizeof(start_code);
- remaining_size -= box_len + sizeof(start_code);
- }
-
- return 0;
-}
-
-/**
* Copies NAL units and replaces length codes with
* H.264 Annex B start codes. On failure, the contents of
* dst_data may have been modified.
@@ -1148,14 +1133,19 @@ static int replace_length_codes(size_t length_code_size,
* the end of its buffer.
*/
static int copy_replace_length_codes(
+ AVCodecContext *avctx,
size_t length_code_size,
- const uint8_t *src_data,
- size_t src_size,
+ CMSampleBufferRef sample_buffer,
uint8_t *dst_data,
size_t dst_size)
{
+ size_t src_size = CMSampleBufferGetTotalSampleSize(sample_buffer);
size_t remaining_src_size = src_size;
size_t remaining_dst_size = dst_size;
+ size_t src_offset = 0;
+ int status;
+ uint8_t size_buf[4];
+ CMBlockBufferRef block = CMSampleBufferGetDataBuffer(sample_buffer);
if (length_code_size > 4) {
return AVERROR_INVALIDDATA;
@@ -1168,11 +1158,19 @@ static int copy_replace_length_codes(
size_t i;
uint8_t *dst_box;
- const uint8_t *src_box;
+
+ status = CMBlockBufferCopyDataBytes(block,
+ src_offset,
+ length_code_size,
+ size_buf);
+ if (status) {
+ av_log(avctx, AV_LOG_ERROR, "Cannot copy length: %d\n", status);
+ return AVERROR_EXTERNAL;
+ }
for (i = 0; i < length_code_size; i++) {
box_len <<= 8;
- box_len |= src_data[i];
+ box_len |= size_buf[i];
}
curr_src_len = box_len + length_code_size;
@@ -1187,12 +1185,19 @@ static int copy_replace_length_codes(
}
dst_box = dst_data + sizeof(start_code);
- src_box = src_data + length_code_size;
memcpy(dst_data, start_code, sizeof(start_code));
- memcpy(dst_box, src_box, box_len);
+ status = CMBlockBufferCopyDataBytes(block,
+ src_offset + length_code_size,
+ box_len,
+ dst_box);
+
+ if (status) {
+ av_log(avctx, AV_LOG_ERROR, "Cannot copy data: %d\n", status);
+ return AVERROR_EXTERNAL;
+ }
- src_data += curr_src_len;
+ src_offset += curr_src_len;
dst_data += curr_dst_len;
remaining_src_size -= curr_src_len;
@@ -1212,16 +1217,15 @@ static int vtenc_cm_to_avpacket(
int status;
bool is_key_frame;
bool add_header;
- char *buf_data;
size_t length_code_size;
size_t header_size = 0;
size_t in_buf_size;
+ size_t out_buf_size;
int64_t dts_delta;
int64_t time_base_num;
+ int nalu_count;
CMTime pts;
CMTime dts;
-
- CMBlockBufferRef block;
CMVideoFormatDescriptionRef vid_fmt;
@@ -1235,82 +1239,42 @@ static int vtenc_cm_to_avpacket(
vid_fmt = CMSampleBufferGetFormatDescription(sample_buffer);
if (!vid_fmt) {
av_log(avctx, AV_LOG_ERROR, "Cannot get format description.\n");
+ return AVERROR_EXTERNAL;
}
int status = get_params_size(avctx, vid_fmt, &header_size);
if (status) return status;
}
- block = CMSampleBufferGetDataBuffer(sample_buffer);
- if (!block) {
- av_log(avctx, AV_LOG_ERROR, "Could not get block buffer from sample buffer.\n");
- return AVERROR_EXTERNAL;
- }
-
-
- status = CMBlockBufferGetDataPointer(block, 0, &in_buf_size, NULL, &buf_data);
- if (status) {
- av_log(avctx, AV_LOG_ERROR, "Error: cannot get data pointer: %d\n", status);
- return AVERROR_EXTERNAL;
- }
-
- size_t out_buf_size = header_size + in_buf_size;
- bool can_reuse_cmbuffer = !add_header &&
- !pkt->data &&
- length_code_size == sizeof(start_code);
-
- av_init_packet(pkt);
-
- if (can_reuse_cmbuffer) {
- AVBufferRef* buf_ref = av_buffer_create(
- buf_data,
- out_buf_size,
- vtenc_free_block,
- block,
- 0
- );
-
- if (!buf_ref) return AVERROR(ENOMEM);
-
- CFRetain(block);
-
- pkt->buf = buf_ref;
- pkt->data = buf_data;
- pkt->size = in_buf_size;
+ status = count_nalus(length_code_size, sample_buffer, &nalu_count);
+ if(status)
+ return status;
- status = replace_length_codes(length_code_size, pkt->data, pkt->size);
- if (status) {
- av_log(avctx, AV_LOG_ERROR, "Error replacing length codes: %d\n", status);
- return status;
- }
- } else {
- if (!pkt->data) {
- status = av_new_packet(pkt, out_buf_size);
- if(status) return status;
- }
+ in_buf_size = CMSampleBufferGetTotalSampleSize(sample_buffer);
+ out_buf_size = header_size +
+ in_buf_size +
+ nalu_count * ((int)sizeof(start_code) - (int)length_code_size);
- if (pkt->size < out_buf_size) {
- av_log(avctx, AV_LOG_ERROR, "Error: packet's buffer is too small.\n");
- return AVERROR_BUFFER_TOO_SMALL;
- }
+ status = ff_alloc_packet2(avctx, pkt, out_buf_size, out_buf_size);
+ if (status < 0)
+ return status;
- if (add_header) {
- status = copy_param_sets(avctx, vid_fmt, pkt->data, out_buf_size);
- if(status) return status;
- }
+ if (add_header) {
+ status = copy_param_sets(avctx, vid_fmt, pkt->data, out_buf_size);
+ if(status) return status;
+ }
- status = copy_replace_length_codes(
- length_code_size,
- buf_data,
- in_buf_size,
- pkt->data + header_size,
- pkt->size - header_size
- );
+ status = copy_replace_length_codes(
+ avctx,
+ length_code_size,
+ sample_buffer,
+ pkt->data + header_size,
+ pkt->size - header_size
+ );
- if (status) {
- av_log(avctx, AV_LOG_ERROR, "Error copying packet data: %d", status);
- return status;
- }
+ if (status) {
+ av_log(avctx, AV_LOG_ERROR, "Error copying packet data: %d", status);
+ return status;
}
if (is_key_frame) {
@@ -1333,6 +1297,7 @@ static int vtenc_cm_to_avpacket(
time_base_num = avctx->time_base.num;
pkt->pts = pts.value / time_base_num;
pkt->dts = dts.value / time_base_num - dts_delta;
+ pkt->size = out_buf_size;
return 0;
}
--
2.7.4
More information about the ffmpeg-devel
mailing list