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path: root/ffmpeg/libavcodec/flac_parser.c
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Diffstat (limited to 'ffmpeg/libavcodec/flac_parser.c')
-rw-r--r--ffmpeg/libavcodec/flac_parser.c66
1 files changed, 49 insertions, 17 deletions
diff --git a/ffmpeg/libavcodec/flac_parser.c b/ffmpeg/libavcodec/flac_parser.c
index e2c6744..ba1f060 100644
--- a/ffmpeg/libavcodec/flac_parser.c
+++ b/ffmpeg/libavcodec/flac_parser.c
@@ -27,11 +27,12 @@
* Each time it finds and verifies a CRC-8 header it sees which of the
* FLAC_MAX_SEQUENTIAL_HEADERS that came before it have a valid CRC-16 footer
* that ends at the newly found header.
- * Headers are scored by FLAC_HEADER_BASE_SCORE plus the max of it's crc-verified
+ * Headers are scored by FLAC_HEADER_BASE_SCORE plus the max of its crc-verified
* children, penalized by changes in sample rate, frame number, etc.
* The parser returns the frame with the highest score.
**/
+#include "libavutil/attributes.h"
#include "libavutil/crc.h"
#include "libavutil/fifo.h"
#include "bytestream.h"
@@ -86,6 +87,8 @@ typedef struct FLACParseContext {
int end_padded; /**< specifies if fifo_buf's end is padded */
uint8_t *wrap_buf; /**< general fifo read buffer when wrapped */
int wrap_buf_allocated_size; /**< actual allocated size of the buffer */
+ FLACFrameInfo last_fi; /**< last decoded frame header info */
+ int last_fi_valid; /**< set if last_fi is valid */
} FLACParseContext;
static int frame_header_is_valid(AVCodecContext *avctx, const uint8_t *buf,
@@ -266,13 +269,12 @@ static int find_new_headers(FLACParseContext *fpc, int search_start)
return size;
}
-static int check_header_mismatch(FLACParseContext *fpc,
- FLACHeaderMarker *header,
- FLACHeaderMarker *child,
- int log_level_offset)
+static int check_header_fi_mismatch(FLACParseContext *fpc,
+ FLACFrameInfo *header_fi,
+ FLACFrameInfo *child_fi,
+ int log_level_offset)
{
- FLACFrameInfo *header_fi = &header->fi, *child_fi = &child->fi;
- int deduction = 0, deduction_expected = 0, i;
+ int deduction = 0;
if (child_fi->samplerate != header_fi->samplerate) {
deduction += FLAC_HEADER_CHANGED_PENALTY;
av_log(fpc->avctx, AV_LOG_WARNING + log_level_offset,
@@ -287,13 +289,25 @@ static int check_header_mismatch(FLACParseContext *fpc,
/* Changing blocking strategy not allowed per the spec */
deduction += FLAC_HEADER_BASE_SCORE;
av_log(fpc->avctx, AV_LOG_WARNING + log_level_offset,
- "blocking strategy change detected in adjacent frames\n");
+ "blocking strategy change detected in adjacent frames\n");
}
if (child_fi->channels != header_fi->channels) {
deduction += FLAC_HEADER_CHANGED_PENALTY;
av_log(fpc->avctx, AV_LOG_WARNING + log_level_offset,
- "number of channels change detected in adjacent frames\n");
+ "number of channels change detected in adjacent frames\n");
}
+ return deduction;
+}
+
+static int check_header_mismatch(FLACParseContext *fpc,
+ FLACHeaderMarker *header,
+ FLACHeaderMarker *child,
+ int log_level_offset)
+{
+ FLACFrameInfo *header_fi = &header->fi, *child_fi = &child->fi;
+ int deduction, deduction_expected = 0, i;
+ deduction = check_header_fi_mismatch(fpc, header_fi, child_fi,
+ log_level_offset);
/* Check sample and frame numbers. */
if ((child_fi->frame_or_sample_num - header_fi->frame_or_sample_num
!= header_fi->blocksize) &&
@@ -398,11 +412,18 @@ static int score_header(FLACParseContext *fpc, FLACHeaderMarker *header)
FLACHeaderMarker *child;
int dist = 0;
int child_score;
-
+ int base_score = FLAC_HEADER_BASE_SCORE;
if (header->max_score != FLAC_HEADER_NOT_SCORED_YET)
return header->max_score;
- header->max_score = FLAC_HEADER_BASE_SCORE;
+ /* Modify the base score with changes from the last output header */
+ if (fpc->last_fi_valid) {
+ /* Silence the log since this will be repeated if selected */
+ base_score -= check_header_fi_mismatch(fpc, &fpc->last_fi, &header->fi,
+ AV_LOG_DEBUG);
+ }
+
+ header->max_score = base_score;
/* Check and compute the children's scores. */
child = header->next;
@@ -418,7 +439,7 @@ static int score_header(FLACParseContext *fpc, FLACHeaderMarker *header)
if (FLAC_HEADER_BASE_SCORE + child_score > header->max_score) {
/* Keep the child because the frame scoring is dynamic. */
header->best_child = child;
- header->max_score = FLAC_HEADER_BASE_SCORE + child_score;
+ header->max_score = base_score + child_score;
}
child = child->next;
}
@@ -429,7 +450,7 @@ static int score_header(FLACParseContext *fpc, FLACHeaderMarker *header)
static void score_sequences(FLACParseContext *fpc)
{
FLACHeaderMarker *curr;
- int best_score = FLAC_HEADER_NOT_SCORED_YET;
+ int best_score = 0;//FLAC_HEADER_NOT_SCORED_YET;
/* First pass to clear all old scores. */
for (curr = fpc->headers; curr; curr = curr->next)
curr->max_score = FLAC_HEADER_NOT_SCORED_YET;
@@ -469,6 +490,9 @@ static int get_best_header(FLACParseContext* fpc, const uint8_t **poutbuf,
&fpc->wrap_buf_allocated_size);
fpc->best_header_valid = 0;
+ fpc->last_fi_valid = 1;
+ fpc->last_fi = header->fi;
+
/* Return the negative overread index so the client can compute pos.
This should be the amount overread to the beginning of the child */
if (child)
@@ -488,8 +512,11 @@ static int flac_parse(AVCodecParserContext *s, AVCodecContext *avctx,
if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
FLACFrameInfo fi;
- if (frame_header_is_valid(avctx, buf, &fi))
+ if (frame_header_is_valid(avctx, buf, &fi)) {
s->duration = fi.blocksize;
+ if (!avctx->sample_rate)
+ avctx->sample_rate = fi.samplerate;
+ }
*poutbuf = buf;
*poutbuf_size = buf_size;
return buf_size;
@@ -628,9 +655,12 @@ static int flac_parse(AVCodecParserContext *s, AVCodecContext *avctx,
}
curr = fpc->headers;
- for (curr = fpc->headers; curr; curr = curr->next)
- if (!fpc->best_header || curr->max_score > fpc->best_header->max_score)
+ for (curr = fpc->headers; curr; curr = curr->next) {
+ if (curr->max_score > 0 &&
+ (!fpc->best_header || curr->max_score > fpc->best_header->max_score)) {
fpc->best_header = curr;
+ }
+ }
if (fpc->best_header) {
fpc->best_header_valid = 1;
@@ -658,13 +688,15 @@ handle_error:
return read_end - buf;
}
-static int flac_parse_init(AVCodecParserContext *c)
+static av_cold int flac_parse_init(AVCodecParserContext *c)
{
FLACParseContext *fpc = c->priv_data;
fpc->pc = c;
/* There will generally be FLAC_MIN_HEADERS buffered in the fifo before
it drains. This is allocated early to avoid slow reallocation. */
fpc->fifo_buf = av_fifo_alloc(FLAC_AVG_FRAME_SIZE * (FLAC_MIN_HEADERS + 3));
+ if (!fpc->fifo_buf)
+ return AVERROR(ENOMEM);
return 0;
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-06 12:47:52 +0000