[FFmpeg-devel] [PATCH] Add ATRAC3+ decoder

[Michael Niedermayer]

On Mon, Oct 14, 2013 at 08:52:04PM +0200, Maxim Polijakowski wrote:
> 
> >>+    const uint8_t *buf  = avpkt->data;
> >>+    int buf_size        = avpkt->size;
> >>+    ATRAC3PContext *ctx = avctx->priv_data;
> >>+    AVFrame *frame      = data;
> >>+    int i, ret, ch_unit_id, ch_block = 0, out_ch_index = 0, channels_to_process;
> >>+    float **samples_p = (float **)frame->extended_data;
> >>+
> >>+    frame->nb_samples = ATRAC3P_FRAME_SAMPLES;
> >>+    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
> >>+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
> >>+        return ret;
> >>+    }
> >>+
> >>+    init_get_bits(&ctx->gb, buf, buf_size * 8);
> >if ((ret = init_get_bits8(&ctx->gb, avpkt->data, avpkt->size)) < 0)
> >     return ret;
> 
> Done.
> 
> >[...]
> >
> >>+
> >>+/**
> >>+ *  @file
> >>+ *  DSP functions for ATRAC3+ decoder.
> >>+ */
> >>+
> >>+#include <math.h>
> >>+
> >>+#include "libavutil/float_dsp.h"
> >>+#include "avcodec.h"
> >>+#include "sinewin.h"
> >>+#include "fft.h"
> >>+#include "atrac3plus.h"
> >>+#include "atrac3plus_data.h"
> >>+
> >>+#define ATRAC3P_MDCT_SIZE (ATRAC3P_SUBBAND_SAMPLES * 2)
> >>+
> >>+static AVFloatDSPContext atrac3p_dsp;
> >This looks strange and is probably incorrect, it probably should be in
> >private context.
> >
> 
> What is wrong with that?

Initialization uses a local per instance flag
(avctx->flags & CODEC_FLAG_BITEXACT)
thus if there are 2 instances, one with the flag set and one not set
a single global context could only be corrct for both if the flag
has no effect and would be unused
so something in this looks wrong, either it shouldt be global or there
should be no local flag passed to it.

avpriv_float_dsp_init(&atrac3p_dsp, avctx->flags & CODEC_FLAG_BITEXACT);

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I am the wisest man alive, for I know one thing, and that is that I know
nothing. -- Socrates
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