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Hi, everyone.<br>
<span style="color: rgb(0, 0, 0); font-family: Arial, 'Liberation
Sans', 'DejaVu Sans', sans-serif; font-size: 14px; font-style:
normal; font-variant: normal; font-weight: normal; letter-spacing:
normal; line-height: 18px; orphans: auto; text-align: left;
text-indent: 0px; text-transform: none; white-space: normal;
widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;
background-color: rgb(255, 255, 255); display: inline !important;
float: none;">I'm trying to use libavcodec to encode a flv video.
Following code is a sample code to generate a mpeg video, it works
well. But after replacing the codec ID with AV_CODEC_ID_FLV1, the
generated video file cannot be played.<br>
</span><br>
I opened the generated file and checked the first 4 bytes (previous
tag size), but it's not 0. I'm curious whether converted packet is
valid flv packet?<br>
Any suggestion is appreciated.<br>
<br>
(Code)<br>
<pre style="margin: 0px 0px 10px; padding: 5px; border: 0px; font-size: 14px; vertical-align: baseline; background-color: rgb(238, 238, 238); font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, serif; overflow: auto; width: auto; max-height: 600px; word-wrap: normal; color: rgb(0, 0, 0); font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: 18px; orphans: auto; text-align: left; text-indent: 0px; text-transform: none; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-position: initial initial; background-repeat: initial initial;"><code style="margin: 0px; padding: 0px; border: 0px; font-size: 14px; vertical-align: baseline; background-color: rgb(238, 238, 238); font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, serif
; background-position: initial initial; background-repeat: initial initial;">void simpleEncode(){
AVCodec *codec = avcodec_find_encoder(AV_CODEC_ID_MPEG1VIDEO);
AVCodecContext *ctx = avcodec_alloc_context3(codec);
ctx->bit_rate = 400000;
ctx->width = 352;
ctx->height = 288;
AVRational time_base = {1,25};
ctx->time_base = time_base;
ctx->gop_size = 10;
ctx->pix_fmt = AV_PIX_FMT_YUV420P;
avcodec_open2(ctx, codec, NULL);
AVFrame *frame = av_frame_alloc();
av_image_alloc(frame->data, frame->linesize, ctx->width, ctx->height, ctx->pix_fmt, 32);
frame->format = ctx->pix_fmt;
frame->height = ctx->height;
frame->width = ctx->width;
AVPacket pkt;
int got_output;
FILE *f = fopen("test.mpg", "wb");
for(int i=0; i<25; i++){
av_init_packet(&pkt);
pkt.data = NULL;
pkt.size = 0;
for(int w=0; w<ctx->width; w++){
for(int h=0; h<ctx->height; h++){
frame->data[0][h*frame->linesize[0]+w]=i*10;
}
}
for(int w=0; w<ctx->width/2; w++){
for(int h=0; h<ctx->height/2; h++){
frame->data[1][h*frame->linesize[1]+w]=i*10;
frame->data[2][h*frame->linesize[2]+w]=i*10;
}
}
frame->pts=i;
avcodec_encode_video2(ctx, &pkt, frame, &got_output);
fwrite(pkt.data, 1, pkt.size, f);
}
}</code></pre>
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