From 0c5670a0e571a3ba0e5e2fc45d5054041e049830 Mon Sep 17 00:00:00 2001 From: Ramiro Polla Date: Mon, 30 Mar 2009 02:54:19 +0000 Subject: [PATCH] mlpdec: Max filter orders for FIR and IIR are 8 and 4 respectively. Originally committed as revision 18230 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/mlp.h | 12 +++++------- libavcodec/mlpdec.c | 11 ++++++----- 2 files changed, 11 insertions(+), 12 deletions(-) diff --git a/libavcodec/mlp.h b/libavcodec/mlp.h index c19b69915e..433f95f6eb 100644 --- a/libavcodec/mlp.h +++ b/libavcodec/mlp.h @@ -50,11 +50,9 @@ /** number of allowed filters */ #define NUM_FILTERS 2 -/** The maximum number of taps in either the IIR or FIR filter; - * I believe MLP actually specifies the maximum order for IIR filters as four, - * and that the sum of the orders of both filters must be <= 8. -*/ -#define MAX_FILTER_ORDER 8 +/** The maximum number of taps in IIR and FIR filters. */ +#define MAX_FIR_ORDER 8 +#define MAX_IIR_ORDER 4 /** Code that signals end of a stream. */ #define END_OF_STREAM 0xd234d234 @@ -67,8 +65,8 @@ typedef struct { uint8_t order; ///< number of taps in filter uint8_t shift; ///< Right shift to apply to output of filter. - int32_t coeff[MAX_FILTER_ORDER]; - int32_t state[MAX_FILTER_ORDER]; + int32_t coeff[MAX_FIR_ORDER]; + int32_t state[MAX_FIR_ORDER]; } FilterParams; /** sample data coding information */ diff --git a/libavcodec/mlpdec.c b/libavcodec/mlpdec.c index a42b5e36a7..8bcbd2129b 100644 --- a/libavcodec/mlpdec.c +++ b/libavcodec/mlpdec.c @@ -433,6 +433,7 @@ static int read_filter_params(MLPDecodeContext *m, GetBitContext *gbp, unsigned int channel, unsigned int filter) { FilterParams *fp = &m->channel_params[channel].filter_params[filter]; + const int max_order = filter ? MAX_IIR_ORDER : MAX_FIR_ORDER; const char fchar = filter ? 'I' : 'F'; int i, order; @@ -440,10 +441,10 @@ static int read_filter_params(MLPDecodeContext *m, GetBitContext *gbp, assert(filter < 2); order = get_bits(gbp, 4); - if (order > MAX_FILTER_ORDER) { + if (order > max_order) { av_log(m->avctx, AV_LOG_ERROR, "%cIR filter order %d is greater than maximum %d.\n", - fchar, order, MAX_FILTER_ORDER); + fchar, order, max_order); return -1; } fp->order = order; @@ -651,7 +652,7 @@ static void filter_channel(MLPDecodeContext *m, unsigned int substr, unsigned int channel) { SubStream *s = &m->substream[substr]; - int32_t filter_state_buffer[NUM_FILTERS][MAX_BLOCKSIZE + MAX_FILTER_ORDER]; + int32_t filter_state_buffer[NUM_FILTERS][MAX_BLOCKSIZE + MAX_FIR_ORDER]; FilterParams *fp[NUM_FILTERS] = { &m->channel_params[channel].filter_params[FIR], &m->channel_params[channel].filter_params[IIR], }; unsigned int filter_shift = fp[FIR]->shift; @@ -661,7 +662,7 @@ static void filter_channel(MLPDecodeContext *m, unsigned int substr, for (j = 0; j < NUM_FILTERS; j++) { memcpy(&filter_state_buffer[j][MAX_BLOCKSIZE], &fp[j]->state[0], - MAX_FILTER_ORDER * sizeof(int32_t)); + MAX_FIR_ORDER * sizeof(int32_t)); } for (i = 0; i < s->blocksize; i++) { @@ -690,7 +691,7 @@ static void filter_channel(MLPDecodeContext *m, unsigned int substr, for (j = 0; j < NUM_FILTERS; j++) { memcpy(&fp[j]->state[0], &filter_state_buffer[j][index], - MAX_FILTER_ORDER * sizeof(int32_t)); + MAX_FIR_ORDER * sizeof(int32_t)); } } -- GitLab