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https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-23 12:43:46 +02:00
dpcm: factor out the stereo flag calculation
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parent
b09c7eefb7
commit
3db8db406f
@ -169,6 +169,7 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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int in, out = 0;
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int predictor[2];
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int ch = 0;
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int stereo = s->channels - 1;
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short *output_samples = data;
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int shift[2];
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unsigned char byte;
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@ -184,11 +185,11 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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switch(avctx->codec->id) {
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case CODEC_ID_ROQ_DPCM:
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if (s->channels == 1)
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predictor[0] = AV_RL16(&buf[6]);
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else {
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if (stereo) {
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predictor[0] = buf[7] << 8;
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predictor[1] = buf[6] << 8;
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} else {
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predictor[0] = AV_RL16(&buf[6]);
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}
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SE_16BIT(predictor[0]);
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SE_16BIT(predictor[1]);
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@ -200,7 +201,7 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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output_samples[out] = predictor[ch];
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/* toggle channel */
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ch ^= s->channels - 1;
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ch ^= stereo;
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}
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break;
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@ -210,7 +211,7 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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in += 2;
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SE_16BIT(predictor[0])
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output_samples[out++] = predictor[0];
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if (s->channels == 2) {
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if (stereo) {
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predictor[1] = AV_RL16(&buf[in]);
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in += 2;
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SE_16BIT(predictor[1])
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@ -223,7 +224,7 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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output_samples[out++] = predictor[ch];
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/* toggle channel */
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ch ^= s->channels - 1;
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ch ^= stereo;
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}
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break;
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@ -234,7 +235,7 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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predictor[0] = AV_RL16(&buf[in]);
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in += 2;
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SE_16BIT(predictor[0]);
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if (s->channels == 2) {
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if (stereo) {
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predictor[1] = AV_RL16(&buf[in]);
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in += 2;
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SE_16BIT(predictor[1]);
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@ -258,7 +259,7 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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output_samples[out++] = predictor[ch];
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/* toggle channel */
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ch ^= s->channels - 1;
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ch ^= stereo;
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}
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break;
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case CODEC_ID_SOL_DPCM:
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@ -271,13 +272,13 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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n1 = (buf[in] >> 4) & 0xF;
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n2 = buf[in++] & 0xF;
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s->sample[0] += s->sol_table[n1];
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if (s->sample[0] < 0) s->sample[0] = 0;
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if (s->sample[0] < 0) s->sample[0] = 0;
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if (s->sample[0] > 255) s->sample[0] = 255;
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output_samples[out++] = (s->sample[0] - 128) << 8;
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s->sample[s->channels - 1] += s->sol_table[n2];
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if (s->sample[s->channels - 1] < 0) s->sample[s->channels - 1] = 0;
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if (s->sample[s->channels - 1] > 255) s->sample[s->channels - 1] = 255;
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output_samples[out++] = (s->sample[s->channels - 1] - 128) << 8;
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s->sample[stereo] += s->sol_table[n2];
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if (s->sample[stereo] < 0) s->sample[stereo] = 0;
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if (s->sample[stereo] > 255) s->sample[stereo] = 255;
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output_samples[out++] = (s->sample[stereo] - 128) << 8;
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}
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} else {
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while (in < buf_size) {
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@ -288,7 +289,7 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
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s->sample[ch] = av_clip_int16(s->sample[ch]);
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output_samples[out++] = s->sample[ch];
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/* toggle channel */
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ch ^= s->channels - 1;
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ch ^= stereo;
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}
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}
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break;
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